Mean Well UHP-350-5 Power Supply
5V 60A · 300W at 5V, not 350W · fanless slim 220 × 62 × 31mm · 90% efficient · active PFC
A 300W 5V supply in a fanless 31mm case — and one whose datasheet names a 450 × 450mm aluminium mounting plate, half again the area the smaller UHP-200 asks for — supplied by Excelled Display, LED display manufacturer and component supplier for global B2B integrators.
Mean Well UHP-350-5 Power Supply at a Glance
What is it? The UHP-350-5 is the 5V model in the MEAN WELL UHP-350 series of slim type enclosed power supplies with active PFC. It delivers a regulated 5V DC output at up to 60A from a fanless case measuring 220 × 62 × 31mm and weighing 0.68kg.
How much power does it deliver? 300W — not the 350W the name suggests. 5V × 60A = 300W. The series number refers to the higher-voltage models: the 12V unit delivers 350.4W, the 15V unit 351W. At 5V you are buying the 300W member of a 350W family, and the gap is 50W, or 14%.
How efficient is it? 90% typical at 5V. That is the lowest efficiency in the UHP-350 series — the range runs from 88.5% at 3.3V up to 94% at 24V and above — and it is the price of converting to a low voltage at high current. Read against the UHP-200-5’s 91% at 5V, the larger model gives up a point of efficiency to deliver 100W more.
Is there a catch to the fanless design? Yes, and this is the fact most listings omit. The UHP-350 series must be installed onto an aluminium plate, or onto a cabinet of the same size, on the bottom. The suggested plate for this series is 450 × 450mm — more than double the area of the 300 × 300mm plate the UHP-200 series specifies, because there is more heat to move. The surface must be even and smooth (or thermal grease applied), and the unit must be firmly mounted at the centre. Full detail below.
What does it take in? A 90–264VAC input, or 127–370VDC, at 47–63Hz. Full-range input means no 115/230V selector switch. Inrush current is a cold-start 30A/115VAC and 60A/230VAC — lower than the smaller UHP-200-5’s 40A/80A, which is not the direction most people expect.
What optional functions does it offer? The same two as the UHP-200: a DC OK signal reporting output status to a monitoring circuit (15Vdc / 10mA resistive load), and a redundant function on the UHP-350R variant, which allows two units in parallel so that if one fails the other is automatically enabled.
What is it used for? The datasheet’s own application list names industrial automation machinery, industrial control systems, mechanical and electrical equipment, electronic instruments and apparatus, household appliances, LED display application, and power source equipment for PoE on the 55V model. Configuration, MOQ and pricing from our sales team.
The UHP-350 Series: Nine Voltages and the 50W the Name Does Not Deliver
The UHP-350 series covers nine voltages from 3.3V to 55V. The three lowest share a 60A current ceiling, and none of them reaches the 350W the family is named for — the 5V model comes closest, at 300W.
| Model | Output voltage | Rated current | Rated power | Efficiency (typ.) |
|---|---|---|---|---|
| UHP-350-3.3 | 3.3V | 60A | 198W | 88.5% |
| UHP-350-4.2 | 4.2V | 60A | 252W | 89% |
| UHP-350-5 | 5V | 60A | 300W | 90% |
| UHP-350-12 | 12V | 29.2A | 350.4W | 91% |
| UHP-350-15 | 15V | 23.4A | 351W | 92% |
| UHP-350-24 | 24V | 14.6A | 350.4W | 94% |
| UHP-350-36 | 36V | 9.75A | 351W | 94% |
| UHP-350-48 | 48V | 7.3A | 350.4W | 94% |
| UHP-350-55 | 55V | 6.3A | 350W | 94% |
Efficiency runs the other way across the same group. At 5V the supply is 90% efficient, against 88.5% at 3.3V and 89% at 4.2V, and against 94% at 24V and above. Low voltage at high current is the hardest conversion to do efficiently, which is why the 5V model is at the bottom of its own series and why it produces more waste heat per watt delivered than any other model in the range.
UHP-350-5 Specifications: Datasheet Parameters for the 5V 60A Model
Transcribed from the MEAN WELL UHP-350 specification sheet (UHP-350-SPEC, revision dated 2024-11-23) for the 5V model. Unless stated otherwise, readings are taken at 230VAC input, rated load and 25°C ambient.
| Parameter | UHP-350-5 specification |
|---|---|
| DC output voltage | 5V, adjustable 4.5 ∼ 5.5V via SVR |
| Rated current | 60A |
| Rated power | 300W (the series name refers to the 12V-and-above models) |
| Ripple & noise (max.) | 200mVp-p at 20MHz bandwidth; the 3.3V model is quoted at 150mVp-p and the 55V model at 300mVp-p |
| Voltage tolerance | ±2.0% (includes set-up tolerance, line regulation and load regulation) |
| Line regulation | ±0.5% |
| Load regulation | ±1.0% from 0% to 100% rated load |
| Set-up / rise time | 2000ms, 80ms/230VAC; 3000ms, 80ms/115VAC at full load |
| Hold-up time (typ.) | 10ms at 230VAC and 10ms at 115VAC, full load |
| Input voltage range | 90 ∼ 264VAC, no selector switch; 127 ∼ 370VDC |
| Input frequency | 47 ∼ 63Hz |
| Power factor (typ.) | PF > 0.94 / 230VAC, PF > 0.98 / 115VAC at full load |
| Efficiency (typ.) | 90% at 5V; the series spans 88.5% at 3.3V to 94% at 24V and above |
| AC current (typ.) | The datasheet prints a single figure for the series, 4A/115VAC and 2A/230VAC, without attributing it to individual models. Treat it as a series-level figure; we will confirm the 5V model’s own value against the current revision on request |
| Inrush current (typ.) | Cold start 30A/115VAC, 60A/230VAC — lower than the smaller UHP-200-5, which is rated 40A/80A |
| Leakage current | <0.75mA / 240VAC |
| Overload protection | 110 ∼ 140% rated output power; hiccup mode, recovers automatically once the fault is removed |
| Over-voltage protection | 5.75 ∼ 6.75V on the 5V model; shuts down the output, re-power required to recover |
| Over-temperature protection | Shuts down output, recovers automatically once temperature falls |
| Cooling | Fanless — free air convection. Requires an aluminium mounting plate; see the installation section |
| DC OK signal | Optional. Collector-shorted signal via optocoupler; contact rating max. 15Vdc / 10mA resistive load |
| Redundant function | Optional (UHP-350R). Two units may be connected in parallel; if one fails the other is automatically enabled |
| Working temperature | −30 ∼ +70°C with derating (refer to the derating curves) |
| Working humidity | 20 ∼ 95% RH non-condensing |
| Storage | −40 ∼ +85°C, 10 ∼ 95% RH non-condensing |
| Temperature coefficient | ±0.03%/°C (0 ∼ 50°C) |
| Vibration | 10 ∼ 500Hz, 5G, 10 min per cycle, 60 min each along X, Y and Z axes |
| Withstand voltage | I/P–O/P 3.75KVAC; I/P–FG 2KVAC; O/P–FG 1.25KVAC |
| Isolation resistance | 100MΩ / 500VDC at 25°C, 70% RH |
| Dimensions (L×W×H) | 220 × 62 × 31mm (Case No. 232C), tolerance ±1mm |
| Weight / packing | 0.68kg per unit; 16pcs / 11.88kg / 0.63CUFT per carton |
| MTBF | 1791.2K hrs min. Telcordia SR-332 (Bellcore); 253.4K hrs min. MIL-HDBK-217F at 25°C |
| Warranty | 3 years (manufacturer’s stated warranty on the datasheet) |
The UHP-350-5 Aluminium Plate: 450 × 450mm, Not the UHP-200’s 300 × 300
The UHP-350 series carries the same installation requirement as the UHP-200 — and the plate is substantially larger, because there is more heat to reject. This is the single most consequential specification on the datasheet and the one reseller listings routinely drop.
| Requirement | What the UHP-350 datasheet specifies |
|---|---|
| Mounting surface | An aluminium plate, or a cabinet acting as the same, on the bottom of the unit |
| Suggested plate size | 450 × 450mm — against 300 × 300mm for the UHP-200 series |
| Surface condition | Must be even and smooth; or coated with thermal grease |
| Mounting position | The unit must be firmly mounted at the centre of the plate |
| Mounting hardware | M3 × 4 screws at the four mounting holes |
| Why it is required | The derating curve and static characteristics are defined on this basis — without it the published ratings do not apply |
Why 450 × 450 and not 300 × 300
The area scales with the heat, not with the wattage. Two factors push this model harder than the UHP-200-5:
- It delivers 100W more. 300W against 200W, so there is simply more energy to remove.
- It is less efficient at doing it. 90% at 5V against 91% on the UHP-200-5. At full load the UHP-350-5 turns roughly 30W into heat, against roughly 20W for the UHP-200-5 — half again as much waste heat, from a case that is only slightly larger.
- That is the whole argument for the bigger plate. The case is 220 × 62 × 31mm against 194 × 55 × 26mm, so the surface area available to radiate and convect has grown by far less than the heat load. The plate makes up the difference.
The 5V model has the lowest no-plate derating curve in the series
The datasheet draws three derating curves, and the second one — ambient temperature without the aluminium plate — is the one that shows why skipping the plate hurts this model specifically. That curve is split by model group, and the grouping places the 5V model on the lowest line of the three: the datasheet labels the curves 230VAC for 12V~48V, 230VAC for 55V, and 110VAC for all models / 230VAC for 3.3V~5V.
UHP-350-5 Slim Fanless Format: 220 × 62 × 31mm and 0.68kg
The UHP-350-5 occupies roughly the same 62mm width and 31mm height as the rest of its series, so a 300W supply fits a channel that would otherwise need an enclosed unit of twice the width. Compared with the UHP-200-5 one step down, the increase in size is modest against the increase in output.
| Dimension | UHP-350-5 | UHP-200-5 |
|---|---|---|
| Length | 220mm | 194mm |
| Width | 62mm | 55mm |
| Height | 31mm | 26mm |
| Weight | 0.68kg | 0.468kg |
| Output | 5V / 60A / 300W | 5V / 40A / 200W |
| Case | Case No. 232C | Case No. 249B |
| Units per carton | 16pcs / 11.88kg / 0.63CUFT | 24pcs / 12.2kg / 0.49CUFT |
| Required plate | 450 × 450mm | 300 × 300mm |
| Cooling | Fanless, honeycomb perforated case | Fanless, honeycomb perforated case |
A 50% output increase for a 13% length increase
- Volume grows far less than output. 300W in a case barely larger than the 200W unit is the argument for the slim format — and it is also why the plate requirement grows more than the case does.
- Nothing rotates. No fan means no bearing to wear, no airflow path to keep clear, and no acoustic noise in a room where people are working. In a fan-cooled supply the fan is typically the first component to fail; here that failure mode does not exist.
- But there is no fan to mask a marginal thermal design. A fan-cooled supply can be installed in a poorly ventilated cabinet and still deliver, at the cost of fan life. The UHP-350-5 cannot. Get the plate and the airflow right at design stage, because there is no component inside that will compensate later.
- Handling counts at this weight. 16 units per 11.88kg carton against 15 per 11.8kg for the smaller RSP-200 — similar carton weight, but here it carries 300W units rather than 200W ones.
UHP-350-5 DC OK Signal and the UHP-350R Redundant Function
The UHP-350 series offers the same two optional functions as the UHP-200, and the same caveat applies to the second one. Both matter for screens that must report their own health or keep running when a supply fails.
DC OK signal — output status to a monitoring circuit
DC OK is a collector-shorted signal produced by an optocoupler inside the supply, indicating output status. When the unit turns on the optocoupler’s collector-emitter pin conducts; when the output fails, the pin goes open. The datasheet’s function manual shows the recommended interface: a 1K pull-up resistor from the DC OK line to the +V rail, feeding the monitoring input. The contact rating is 15Vdc / 10mA resistive load.
- What it gives you: a per-supply status line so a failed supply is identified rather than inferred from a dark section of screen — the difference between a two-minute diagnosis and a site visit.
- The 1K pull-up in the datasheet is the reference design. Follow it rather than inventing an interface; the optocoupler is a small signal device and the resistor sets the current through it.
- It is a status line, not a measurement. It reports on or off. It will not tell you the output voltage, the load current or the reason for a fault.
Redundant function — the UHP-350R parallel variant
The UHP-350R has a built-in redundant function and can be connected two units in parallel. The datasheet states that for parallel applications, when one power supply cannot work, the other is automatically enabled, preventing a system crash and providing system reliability.
If a section genuinely needs more than 300W at 5V, split it into independently supplied sections or move to a higher-current model rather than paralleling units for wattage. The UHP-500-5 power supply and the RSP-500-5 both step up from here.
UHP-350-5 vs UHP-200-5: Same Family, 100W More, One Point Less Efficiency
Choosing between these two is the most common decision in the UHP slim range: the same fanless format, the same 5V output, the same optional functions, and a 100W step between them. The trade is not only size.
| Parameter | UHP-350-5 | UHP-200-5 |
|---|---|---|
| Output | 5V / 60A | 5V / 40A |
| Rated power | 300W | 200W |
| Ripple & noise | 200mVp-p | 200mVp-p |
| Efficiency (typ.) | 90% | 91% |
| Waste heat at full load | ≈30W | ≈20W |
| Dimensions | 220×62×31mm | 194×55×26mm |
| Weight | 0.68kg | 0.468kg |
| Required plate | 450×450mm | 300×300mm |
| No-plate derating curve at 230VAC | Lowest group (with 3.3V) | Lowest group (with 3.3V) |
| Inrush current | 30A/115VAC, 60A/230VAC | 40A/115VAC, 80A/230VAC |
| Input range | 90∼264VAC | 90∼264VAC |
| Leakage current | <0.75mA | <0.75mA |
| MTBF — Telcordia | 1791.2K hrs | Not quoted |
| MTBF — MIL-HDBK-217F | 253.4K hrs | 257K hrs |
| EN61558-1 / -2-16 | Listed as approved | Stated as design reference |
| DC OK / redundant options | Yes | Yes |
How to choose between them in one line each
- Choose the UHP-350-5 when the 5V load genuinely needs more than 40A, when a single supply per section is preferred over splitting the bus, and when a 450 × 450mm plate can be provided. The Telcordia MTBF figure and the EN61558 approvals are additional arguments in its favour.
- Choose the UHP-200-5 when 200W covers the section, when the plate that can be fitted is only 300 × 300mm, when the lower 194 × 55 × 26mm envelope matters, or when the last point of efficiency is worth having.
- Do not choose on the name. A UHP-350-5 is a 300W 5V supply, not a 350W one. Neither model is what its series number implies at 5V, and the 200W unit is honest where the 350W unit is not.
How Many LED Modules Can One UHP-350-5 Power?
No supplier can answer this without knowing your module. The count depends on the maximum power rating of your LED module from its own datasheet, the number of modules on the supply, and the thermal headroom you leave — which on this supply depends on the mounting plate as much as on the load.
- Start from the real rating. 300W at 5V, which is 60A — not 350W.
- Apply a load ceiling. A common planning rule in LED cabinet builds is to keep continuous load at or below about 80% of rated output — roughly 240W, or 48A, on a UHP-350-5. This is an engineering convention rather than a MEAN WELL figure; confirm it against your own project’s thermal and warranty conditions.
- Divide by the module’s maximum power, taken from the module datasheet rather than a marketing page — full white is the condition a screen is commissioned under.
- Confirm the mounting surface first. Read the derating curve that matches the installation. On this model the answer changes materially between with-plate and without-plate, because the 5V variant sits on the lowest curve when no plate is fitted.
- Check the current path. 48A still has to leave through the terminal block and reach the modules. Confirm wire gauge, terminal rating and the number of feeds.
- Check the capacitance on the 5V rail. If the cabinet carries a large capacitor bank, raise it at quotation so the start-up behaviour can be confirmed.
Worked as an Illustrative Example — substitute your own module figures; these numbers are for the arithmetic only:
| Step | Illustrative calculation |
|---|---|
| Supply rating | 300W / 60A at 5V |
| Usable at 80% planning ceiling | 240W / 48A |
| Module maximum power (illustrative) | 25W per module |
| Modules per supply (240 ÷ 25) | 9 modules, with 15W of the usable budget unspent |
| Heat into the cabinet at that load | ≈27W at 90% efficiency — a figure that has to be removed by the plate and the cabinet airflow, not by a fan |
For the control and signal side of the same cabinet, the LED control system collection covers how sending cards, receiving cards and processors are powered and wired alongside the supplies.
UHP-350-5 Wiring: TB1 AC Input, Twin DC Output Blocks and CN10
The UHP-350-5 uses the same terminal arrangement as the UHP-200-5: one AC input block, two separate DC output blocks, and a signal connector for the optional DC OK function.
| Block | Pin | Assignment | Practical note |
|---|---|---|---|
| TB1 — AC input | 1 | AC/L — live | Mains live input |
| 2 | AC/N — neutral | Mains neutral input | |
| 3 | Frame ground (FG) | Bond to the cabinet earth; do not omit | |
| TB2 / TB3 — DC output | 1, 2 | DC OUTPUT −V | Two terminals, shared negative rail |
| 3, 4 | DC OUTPUT +V | Two terminals, shared positive rail | |
| CN10 — DC OK | 1 | DC COM | Optocoupler return |
| 2 | DC OK +V | Optocoupler collector; 15Vdc / 10mA max |
Terminal hardware, as specified on the datasheet: the AC input block is a DEGSON DG28C-B-03P with a maximum mounting torque of 5kgf-cm; the DC output terminals are TB-HTP-200-40A with a maximum torque of 8kgf-cm. The DC OK connector is a JST B2B-PH-K-S or equivalent, mating with a JST PHR-2 housing and JST SPH-002T-P0.5S terminals. Tightening beyond the stated torque damages the block, and on a 60A output a loose terminal is a heat source.
One detail in the copy of the datasheet we hold: the third AC terminal’s label does not render legibly in our extract, though the block is a three-pin AC input with live and neutral at pins 1 and 2. Confirm the third terminal against the marking printed on the unit itself before wiring.
There is no input voltage switch to set
The UHP-350-5 is full-range 90–264VAC with no selector switch. Nothing to select and nothing to get wrong, and one part number covers both 120V and 230V sites. The static characteristic curve falls away below about 100VAC, so a site with a persistently low supply is worth checking against that curve before the specification is fixed.
Split the load across both output blocks
At 60A, use both +V and both −V terminals and keep the DC run to the first module as short as the cabinet allows. At this current the terminal contact resistance and local heating are the practical limits rather than the supply’s own regulation. Note that this model, like the UHP-200-5, has no remote sense — if the run is long, the drop is yours to manage with conductor size, not the supply’s to correct.
Mount it on the plate before anything else
Sequence matters on this supply. The 450 × 450mm aluminium plate, or a cabinet surface of equivalent area, has to be in place before the unit is commissioned, because the rating depends on it. Mount at the centre of the plate with M3 × 4 screws, on a smooth even surface, with thermal grease if the finish is not bare and flat. Then leave the honeycomb perforated face clear so convection can move air across the case.
The same wiring discipline applies to the control hardware inside the cabinet. Our guides to the MCTRL660 LED display controller and the Colorlight X2 LED video processor cover the signal side, and the Huidu HD-A5 LED display player covers standalone playback for screens that run without a PC.
UHP-350-5 Active PFC Architecture and Protection Loops
The UHP-350 datasheet includes an official block diagram, which is the clearest available evidence of how this supply is built and what protection it carries.
| Stage | What the block diagram shows |
|---|---|
| Input | EMI filter and rectifier, with frame ground (FG) brought out |
| PFC circuit | Active PFC stage — this is what produces the PF > 0.94 at 230VAC and the EN61000-3-2 harmonic compliance. Switching frequency 65KHz |
| Power switching | Primary switching stage, PWM frequency 70KHz ∼ 90KHz |
| Output | Rectifiers and filter producing the regulated +V / −V output |
| Detection & control | A detection circuit feeding a control block that supervises the whole chain |
| Protection loops | O.L.P. (overload), O.T.P. (over-temperature) and O.V.P. (over-voltage) are drawn as separate feedback loops into the control block |
| Optional functions | DC OK function and Redundant function are shown on the diagram as built-in circuit blocks — which is WHY the parallel-redundant behaviour is a designed function rather than an improvised external arrangement |
Why the block diagram matters for specification
- Active PFC is visible, not just claimed. A passive PFC design would show a large inductor in the input path with no switching stage before the main converter. The diagram shows a distinct PFC circuit between the rectifier and the power switching stage, which is the architecture that produces power factor above 0.94 rather than the 0.6–0.7 of an uncorrected supply.
- The three protection loops are separate. OLP and OTP both self-recover; OVP requires a re-power. Seeing them as distinct loops into the control block explains why the three behave differently in the field, which is the subject of the troubleshooting section.
- The redundant function is drawn inside the supply. That is why the UHP-350R can be paralleled and a standard unit cannot, and why the datasheet’s parallel rule about maximum load has to be respected rather than worked around.
- Two switching frequencies, two sources of noise. A 65KHz PFC stage and a 70–90KHz PWM stage are both inside the case. If a screen shows periodic artefacts, knowing both frequencies exist gives an engineer two places to look rather than one.
UHP-350-5 Certifications: EN61558 Approved and Heavy Industry Immunity
The UHP-350-5 carries a stronger set of safety approvals than the UHP-200-5, and one distinction between the two datasheets is worth stating plainly because it is easy to misread as identical.
| Item | Detail from the UHP-350 datasheet (revision dated 2024-11-23) |
|---|---|
| Safety standards | UL 62368-1, TUV BS EN/EN62368-1, BS EN/EN60335-1 (except 55V), BS EN/EN61558-1, BS EN/EN61558-2-16, GB 4943.1, BSMI CNS15598-1, EAC TP TC 004, BIS IS13252(Part1)/IEC60950-1 (except 4.2V/15V/48V/55V) approved; design refers to AS/NZS 61558.1/2.16 and AS/NZS 62368.1 |
| Withstand voltage | I/P–O/P 3.75KVAC; I/P–FG 2KVAC; O/P–FG 1.25KVAC |
| EMC emission | Compliance to BS EN/EN55032, GB17625.1, GB/T 9254.1, Class B, BS EN/EN55014, BS EN/EN61000-3-2, -3, BSMI CNS15936, EAC TP TC 020 |
| EMC immunity | Compliance to BS EN/EN61000-4-2, 3, 4, 5, 6, 8, 11; BS EN/EN61000-6-2 (BS EN/EN50082-2), BS EN/EN55035, heavy industry level, EAC TP TC 020 |
| Isolation resistance | 100MΩ / 500VDC at 25°C, 70% RH |
| MTBF | 1791.2K hrs min. Telcordia SR-332 (Bellcore); 253.4K hrs min. MIL-HDBK-217F at 25°C |
EN61558-1 and -2-16: approved here, a design reference on the UHP-200
BIS IS13252 covers the 5V model
The Indian BIS approval, IS13252(Part1)/IEC60950-1, carries an exclusion list of 4.2V, 15V, 48V and 55V. The 5V model is not excluded. For projects in India or those specifying to BIS, that is a practical point in this model’s favour, and one that is easy to miss because the exclusion list sits in the same cell as the approval.
Heavy industry immunity, and what criteria it implies
The UHP-350-5 is tested to BS EN/EN61000-6-2 (BS EN/EN50082-2) at heavy industry level — the same classification as the UHP-200, and a step above the light industry level of the RSP models. On a screen sharing a supply with welders, motors or switched inductive loads, that classification is the specification that predicts whether the image stays clean.
When the UHP-350-5 Is the Wrong Power Supply
A page that cannot tell you when not to buy something is a catalogue entry, not advice. The UHP-350-5 is the right answer for 300W of 5V in a space-constrained, vibration-exposed or monitoring-critical installation, and clearly wrong in the following cases:
| Situation | Why the UHP-350-5 does not fit |
|---|---|
| The plate can only be 300 × 300mm | This series specifies 450 × 450mm. With a smaller plate the published ratings no longer apply, and the 5V model sits on the weakest no-plate derating curve in the range. The UHP-200-5 is rated for a 300 × 300mm plate. |
| Expecting 350W because of the model number | The 5V model delivers 300W at 60A. The 350W belongs to the 12V-and-above models. |
| Expecting 600W from two UHP-350R units in parallel | The datasheet states that in parallel operation the maximum load must not exceed the rated power of any one PSU. The pair gives 300W with a spare, not 600W. |
| Humid, coastal or condensation-prone site | The UHP-350 series does not list a conformal coating option. The RSP series does, as the -CC suffix on selected models. |
| 5V load above 300W per supply section | The 60A ceiling is the limit of this model. Step up to the UHP-500-5 power supply or split the cabinet into separately supplied sections. |
| The screen must ride through a mains dip | Hold-up is 10ms at full load. That requirement is solved with a UPS or DC-side hold-up, not by changing supply model. |
| Long DC runs expecting the supply to correct the drop | There is no remote sense on this model. At 5V and 60A the voltage drop along a long run is significant and must be managed with conductor size or multiple feeds. |
| Efficiency is the deciding factor | 90% at 5V is the lowest in the UHP-350 series and one point below the UHP-200-5. If waste heat in a sealed cabinet is the constraint, the smaller model at 91% or a higher-voltage architecture is a better answer than a bigger 5V supply. |
| No PFC or harmonic requirement, and cost decides | PFC is much of what you are paying for. An LRS-350-5 gives 300W of 5V for less money where nothing in the specification demands PFC. |
Where the power supply is the wrong component to be choosing at all, the constraint is usually elsewhere in the system. On the indoor product side, pages such as the P3.91 rental LED display and the P2.5 indoor LED display set out the module-level specifications those decisions start from.
UHP-350-5 Troubleshooting: Plate Derating, Hiccup Mode and DC OK
On this supply the most common field problem is not a fault at all — it is a rating that no longer applies because the mounting condition is wrong. Work through these in order.
The screen dims or the supply shuts down as the cabinet warms up
- Possible cause: insufficient heatsinking. Either no aluminium plate, a plate smaller than 450 × 450mm, a painted or uneven surface, or the unit mounted off-centre rather than at the centre of the plate.
- How to check: measure case temperature and cabinet ambient, and compare against the derating curve for the actual mounting condition. The datasheet provides a separate curve for operation without the aluminium plate — and the 5V model sits on the lowest line of that chart, so read the one labelled for the 3.3V~5V group.
- Fix: fit the plate, or fit a larger one, mount at the centre, and use thermal grease if the surface is not bare and smooth. This is the first thing to check on this model before suspecting the supply itself.
Output drops out and recovers on its own, repeatedly
- Possible cause: overload hiccup mode at 110–140% of rated power, or over-temperature protection. Both recover automatically, so both look identical from outside — the block diagram shows them entering the control block on separate loops, but from outside there is no difference.
- How to check: measure DC current at full white, then case temperature and ambient. A clamp meter and a thermometer usually separate the two.
- Fix: if current exceeds the planning ceiling, split the load. If the unit is hot, fix the mounting and airflow — this supply has no fan to mask a marginal thermal design.
No output at all, and it stays off after a power cycle
- Possible cause: over-voltage protection has latched. OVP trips between 5.75V and 6.75V on the 5V model, shuts the output down and requires a re-power to recover — unlike overload and over-temperature, which both self-recover.
- How to check: remove the load and re-power. If the output returns with no load connected, the trip was load-related rather than a supply failure.
- Fix: correct what drove the output above the OVP threshold — typically a load fault or a wiring error — before reconnecting.
The DC OK signal reads “fail” while the screen appears to work
- Possible cause: the monitoring circuit is miswired or the optocoupler load exceeds its rating. DC OK switches a collector-emitter output rated at 15Vdc / 10mA resistive load, and the datasheet’s reference interface uses a 1K pull-up to +V.
- How to check: verify the wiring on CN10 (pin 1 DC COM, pin 2 DC OK +V) and confirm the external load is within the contact rating.
- Fix: follow the datasheet’s 1K pull-up arrangement and drive a logic input rather than a relay coil or lamp. If the signal says fail and the output is genuinely present, the sense circuit is the fault, not the supply.
The screen takes two to three seconds to come on after mains is applied
- Possible cause: nothing is faulty. Set-up is 2000ms at 230VAC and 3000ms at 115VAC, with an 80ms rise time.
- How to check: measure the delay from mains applied to output stable and compare with the datasheet figure for the site voltage.
- Fix: no fix required if the delay matches specification. If control logic assumes supplies are ready sooner, adjust the sequence timing rather than replacing hardware.
Screen brightness drops or pixels discolour at the far end of a run
- Possible cause: voltage drop along the DC path, not a supply fault. At 5V and up to 60A, cable resistance takes a proportionally large bite out of the delivered voltage.
- How to check: measure voltage at the supply terminals and again at the input of the last module on the run. The difference is the drop.
- Fix: shorten the run, increase the conductor cross-section, or split the feed. Then trim the SVR adjustment so the module input reads its specified 5V under load — not so the supply terminal reads 5V. This model has no remote sense to correct the drop for you.
UHP-350-5 Datasheet and Series Documentation
The documents below are the manufacturer’s own files, hosted by MEAN WELL. They are the reference we work from, and the correct place to verify any specification quoted on this page — including the 450 × 450mm plate requirement and the three derating curves.
| Document | What it covers |
|---|---|
| UHP-350 series datasheet (PDF) | Full specification table for all nine voltage models, the three derating curves, static characteristic, block diagram, mechanical drawing, terminal assignment, function manual and the installation section covering the aluminium plate |
| UHP-350 series product page | All voltage variants with their individual model datasheets, certificates and the DC OK and redundant function options |
| Installation manual | Manufacturer installation guidance for the UHP slim series |
MEAN WELL prints a serial number on each unit that can be traced on the manufacturer’s own website. That is the authoritative way to confirm a batch’s provenance and production date — more reliable than any listing photograph, including ours.
Mean Well UHP-350-5: Frequently Asked Questions
QHow many watts is the Mean Well UHP-350-5?
300W, not 350W. At 5V and 60A the output is 300W. The series number matches the higher-voltage models, where the 12V unit delivers 350.4W and the 15V unit 351W. The 5V model is limited by the shared 60A current ceiling, so the gap between its name and its rating is 50W, or 14%.
QDoes the UHP-350-5 need to be mounted on an aluminium plate?
Yes. The datasheet installation section states that to meet the derating curve and static characteristics, the UHP-350 series must be installed onto an aluminium plate, or a cabinet of the same size, on the bottom. The suggested plate is 450 by 450mm with an even smooth surface, and the unit must be mounted at the plate’s centre with M3 by 4 screws. A separate lower derating curve applies without the plate.
QDoes the UHP-350-5 have a fan?
No. It is cooled by free air convection through a honeycomb perforated case, with no fan and no moving parts. The trade-off is the mounting plate requirement: because there is no fan, the mounting surface has to carry roughly 30W of heat away at full load.
QWhat is the efficiency of the UHP-350-5?
90% typical at the 5V output, measured at 230VAC input and rated load. That is the lowest efficiency in the UHP-350 series, which runs from 88.5% at 3.3V up to 94% at 24V and above, and one point below the smaller UHP-200-5 at 91%.
QWhat is the difference between the UHP-350-5 and the UHP-200-5?
Output, size and the required plate. The UHP-350-5 delivers 300W at 5V and 60A in a 220 by 62 by 31mm case weighing 0.68kg and requires a 450 by 450mm aluminium plate. The UHP-200-5 delivers 200W at 5V and 40A in a 194 by 55 by 26mm case weighing 0.468kg, requires a 300 by 300mm plate, and is slightly more efficient at 91%. Both are fanless and both offer DC OK and redundant options.
QCan two UHP-350R units be paralleled to get 600W?
No. The UHP-350R has a built-in redundant function allowing two units in parallel, but the datasheet states that in parallel operation the maximum load should not be greater than the rated power of any one PSU. Two units give 300W with a spare for redundancy, not 600W of capacity.
QWhat is the DC OK signal on the UHP-350?
DC OK is an optional collector-shorted signal produced by an optocoupler inside the supply that indicates output status. The collector-emitter pin conducts when the supply is on and goes open when it fails. The contact rating is 15Vdc at 10mA resistive load, brought out on connector CN10, and the datasheet’s reference interface uses a 1K pull-up resistor to the positive rail.
QDoes the UHP-350-5 need a 115V or 230V selector switch set?
No. It accepts a 90 to 264VAC input with no selector switch, and also accepts 127 to 370VDC. Cold-start inrush current is 30A at 115VAC and 60A at 230VAC, which is lower than the smaller UHP-200-5 at 40A and 80A.
QHow do I wire the UHP-350-5?
TB1 is the AC input with live at pin 1 and neutral at pin 2. TB2 and TB3 are the DC output blocks: pins 1 and 2 are DC negative and pins 3 and 4 are DC positive. CN10 carries the optional DC OK signal on pin 1 (DC COM) and pin 2 (DC OK +V). The output is adjustable between 4.5V and 5.5V using the SVR control.
QWhat is the overload protection behaviour of the UHP-350-5?
Hiccup mode at 110 to 140% of rated output power, recovering automatically once the fault is removed. Over-temperature protection also recovers automatically. Over-voltage protection is the exception: it trips between 5.75V and 6.75V, shuts the output down and requires a re-power to recover.
QIs the UHP-350-5 approved to EN61558?
Yes. The UHP-350 datasheet lists BS EN/EN61558-1 and BS EN/EN61558-2-16 among the approved safety standards, alongside UL 62368-1, TUV BS EN/EN62368-1 and BS EN/EN60335-1. This differs from the UHP-200 datasheet, where the EN61558 reference appears only as a design reference rather than an approval.
QWhat is the MTBF of the UHP-350-5?
1791.2K hours minimum on Telcordia SR-332 (Bellcore), and 253.4K hours minimum on MIL-HDBK-217F at 25 degrees Celsius. The smaller UHP-200 datasheet quotes only the MIL figure and no Telcordia number. MTBF is a calculated prediction rather than a measured service life, and the two methods give answers about seven times apart on the same unit.
Excelled Display supplies MEAN WELL power supplies alongside the modules, cabinets and control hardware they run with, so the thermal path, the mounting condition and the screen specification are confirmed together rather than in isolation. For the rest of the chain, see the LED control system collection, the outdoor LED display range and the LED display manufacturing process behind them.
Related reading: Mean Well UHP-200-5 power supply · Mean Well UHP-500-5 power supply · Mean Well RSP-500-5 power supply · Mean Well LRS-350-5 power supply · MCTRL660 LED display controller