Albright HV500 High Voltage Contactor for Power Distribution Units
A power distribution unit (PDU) routes DC power to the loads that need it. The contactor inside decides when each branch is connected. Albright HV500 is a hermetically sealed contactor for 12 V to 1000 V DC and up to 500 A thermal rating.
Try the main contactor
Pick a coil option and an auxiliary switch, then switch the coil on and off. Tick 'Main contact sticks' to see why the mirror contact exists. The contactor follows the coil. The meters and the see-through view show what Albright states for each coil type.
Coil power
0 W
Load power (example values you set)
0 kW
ContactorOpen
Coil power now0 W
PhaseIdle
What each function does
Coil option
PWM coil economiser
A contactor needs a lot of coil power for a moment to close, and far less to stay closed. The PWM economiser board is built into the HV500 at the factory and does this for you.
- Pull-in. The coil gets full power, 27 W, and the contacts close in under 20 ms.
- Holding. The board switches the coil supply rapidly, so average coil power falls to 3 W. The contactor stays closed with about a ninth of the pull-in power.
- Release. When the supply is removed the contacts open in under 5 ms. With the PWM board fitted, back EMF is 0 V and the coil has suppression.
Why it matters: less heat in the coil and less drain on the battery or auxiliary supply. It works with coil voltages from 12 to 96 V DC, and the board has reverse-polarity protection if the red and black leads are swapped.
Keep in mind: PWM needs a smooth DC supply and does not work with a ramped supply voltage. The sealing covers the PWM circuit too.
Coil option
Magnetic latching
A permanent magnet inside the coil assembly holds the contacts in their last position. The coil only works when you change state.
- Close. Send a pulse of about 500 ms: positive to the red lead, negative to the black lead. The coil draws 12 W during the pulse.
- Hold. Nothing. The contactor stays closed with zero power.
- Open. Send a reverse-polarity pulse of 200 to 500 ms: negative to red, positive to black.
Why it matters: zero power in a stationary application. That helps where a battery system sits closed for long periods, or where coil heat is a problem.
Keep in mind: latching contactors are not failsafe. If control power disappears, the contactor does not open by itself. Design the system with that in mind.
Coil option
Intermittent duty
An intermittent (INT) coil is for switching on load, or for customers who bring their own PWM circuit.
- Use your own PWM at 10 kHz or higher. Albright recommends 15 to 20 kHz for best performance.
- For short-duty uses such as pump control, contact Albright Technical.
Not sure which coil suits your system? Send us the application and we ask Albright.
Auxiliary option
The mirror contact: a status signal you can trust
The problem: switching the coil off is a command. It does not prove that the main contacts opened. Heavy switching can leave main contacts stuck together, and then the battery stays connected although the system thinks it is off.
The solution: the optional auxiliary switch comes as normally open (white wires), normally closed (blue wires) or mirror, normally closed (orange wires). The mirror contact is linked to the main power contacts. It is closed only when the main contacts are open, so it gives your controller proof, not just a command, that the load side is disconnected. Try it in the demo above: choose Mirror as the auxiliary switch, tick 'Main contact sticks (fault)', then power the coil on and off.
Albright states that the mirror contact gives a failsafe status signal of the main contacts, in normal running and in a fault. It follows EN 60947-4-1 Annex F, and EN 60947-5-1 Annex L as a highly reliable way to monitor contactor status. The demo shows the principle only. For comparison, the normally open and normally closed options are shown as following the contactor operation; ask us how they behave in your application. The auxiliary switch is rated 1 A at 24 V DC resistive, with a minimum of 100 mA at 12 V.
What to check when you choose a contactor for a PDU
Current and conductor
Albright gives 250 A continuous with 50 mm² (1-1/0 AWG) cables and up to 500 A with 190 mm² (350 MCM) busbars. Thermal ratings depend on conductor size.
Capacitive loads
If your PDU has capacitors, Albright says pre-charging is required. Plan the pre-charge before you size the contactor.
Frequent switching
Silver alloy tips are an option when the contactor switches load often. Albright gives make and break limits; check them for your voltage and current.
Easy to mount and connect
Main terminals are M6 or M8 female, or M8 or M10 male. The bracket rotates to six angles and an optional terminal guard protects the studs.
Key data
| Rated contact voltage | 12 V – 1000 V DC |
|---|---|
| Current | 250 A continuous with 50 mm² (1-1/0 AWG) cables; up to 500 A with 190 mm² (350 MCM) busbars |
| Coil voltages | 12, 24, 36, 48, 60, 72, 84, 96 V DC |
| Operating temperature | −45 °C to +85 °C (higher possible with current derating) |
| Shock and vibration | 20 G peak shock; 80–2000 Hz sinusoidal vibration, 20 G peak |
| Mechanical life | Main contacts over 10⁶ cycles |
| Insulation and dielectric | Over 200 MΩ; 4000 V DC withstand, leakage under 1 mA |
| Weight | Switch 400 g, bracket 20 g |
| Mounting | Rotatable bracket with six angles |
| Recognition | UL Recognised (product status is shown on Albright's website) |
Where it is used
Albright lists power distribution units as one of the typical applications of the HV series. Tell us about your PDU and we help you choose terminals, coil and auxiliary switch.
Design notes from the manufacturer
Capacitive loads
If your application has capacitors, pre-charging is required.
Latching is not failsafe
A magnetic latching coil stays in its last state without power. Plan the system with that in mind.
Smooth DC for PWM
The PWM board needs a smooth DC supply and does not work with a ramped supply voltage.
Verify in your application
Performance data is a guide. Derating may be needed, and Albright advises confirming actual performance in the end application.
Tell us your PDU and we help you pick the unit
Send us voltage, current per branch, load type and switching frequency. Quoted prices are available for multiple units. Need one unit for a prototype? Order it in the webshop.
Questions
Is it a safety device?
HV500 is a contactor for switching DC loads. Safety functions and system design stay with the equipment designer.
Can it switch under load?
Yes, within the limits Albright gives for make and break current. Silver alloy tips are available for frequent load switching. Check the data for your current and voltage.
Which coil type should I choose?
PWM economiser saves holding power. Magnetic latching uses no power while stationary. Intermittent coils need your own PWM circuit. Tell us the application and we help you decide.
Can it be repaired?
No. Because of the hermetic sealing, HV contactors are not serviceable.
Which terminals can I choose?
Albright offers main contacts as M6 or M8 female, or M8 male (standard) and M10 male. Tell us your cable or busbar and we help you choose.
Albright HV500 is developed and manufactured by Albright International Ltd. It is supplied by MK-Controls Oy, an Albright distributor. Values on this page are from the Albright HV500 catalogue and may change without notice. The animation is a simplified illustration.