MurrelektronikMCS40-3x400-500/24Three-Phase Switch Mode Power Supply, 360–550 V AC In, 24 V DC / 40 A Out, Adjustable 24–28 V, 91% Efficient

Product Description

A three-phase industrial switch mode power supply: 360–550 V AC in, 24 V DC out at 40 A. Murrelektronik’s article number is 85099, and the unit’s own front label confirms it — “SWITCH MODE POWER SUPPLY, ART. NO. 85099”, “INPUT 3×400-500VAC”, “OUTPUT DC24V/40A”.

Type designation decoded — the “40” is amps, not watts

MCS = Murrelektronik’s control-cabinet switch mode series · 40 = 40 A output current · 3×400-500 = three-phase, 400–500 V AC nominal · /24 = 24 V DC output.

People routinely read the 40 as a wattage. It is not. This is a 40 amp supply — roughly 960 W of usable 24 V — which is a different class of unit entirely from a 40 W brick. Murrelektronik does not publish an output wattage figure for this article, so we quote the amps that are published and leave the watts to your own arithmetic.

Output

24 V DC SELV, regulated to ±1% and adjustable from 24 to 28 V — the adjustment range is there so you can lift the rail slightly to compensate for volt-drop on long DC runs to remote I/O or valve banks. Continuous output is 40 A at +60 °C, rising to 46 A at +40 °C, so if your cabinet runs cool you have genuine headroom. Residual ripple is 20 mV rms maximum with switching spikes to 150 mV peak-to-peak. Efficiency is 91%.

Input and protection

Three-phase 360–550 V AC, 50–60 Hz, drawing 3 x 1.7 A. Inrush is limited to 4 A maximum after 1 ms, and external primary fusing should be 3 x 4 A maximum. Mains-failure bridging (hold-up) is up to 8 ms at 440 V AC — enough to ride through a brief dip without dropping a PLC.

The switch-off mode link — a real design decision

The supply is short-circuit and overload protected, and a front plug link selects the behaviour: automatic restart, or definite latching shutdown. The label on the unit reads “OFF / ON AUTORESTART”, so the setting is visible without opening anything. This matters more than it sounds. Auto-restart keeps a nuisance overload from stopping the plant, but it also means a persistent fault causes endless retry cycles; latching shutdown forces a human to look at the fault before the rail comes back. Choose deliberately, and record which way it is set.

Parallel and series capability

Up to five units in parallel for more current, or two in series for 48 V. Note what is not provided: Murrelektronik documents only a green LED indicating output voltage present. There is no DC-OK relay contact or signalling output published for this article, so if your design needs a power-good signal into the PLC you will have to monitor the rail yourself.

Mounting — not a DIN-rail unit

242 x 106 x 270 mm (H x W x D), about 4.5 kg. Mounting is four M4 screws on an 81 x 230 mm rectangle — screw-plate fixing, not DIN rail. Check this before you plan the panel: a 40 A three-phase supply of this vintage bolts to the backplate. Connections are pluggable green terminal blocks, with input on L1/L2/L3 (terminals 4/3/2) and output on terminals 8+/7+/6−/5−.

Environment and standards

Operating 0 to +60 °C, storage −25 to +85 °C, 5–95% RH non-condensing. Standards: EN 60950-1, EN 61204-3, EN 55022 Class B. EAN 4048879080460.

One identity check worth making

Murrelektronik lists a second article, 850808, “MCS 40-3X400-500/24 MIT PFC” — the same type designation but with power factor correction. Article 85099’s datasheet says nothing about PFC. The two are not the same product, and the type designation alone will not tell them apart. The label on this unit clearly reads ART. NO. 85099, so this is the non-PFC version. If your specification calls for PFC, this is not the right article number.

Interchange and searching

Also written MCS40-3X400-500/24, MCS 40-3×400-500/24, MCS-40-3×400-500-24 and by the article number 85099. Commonly searched as “Murr 40A power supply”, “Murrelektronik three phase 24V power supply” and “MCS power supply 3 phase”.