2x 4A 12V DC Output rack-mount power supply with VRLA battery support and monitoring

  • 2x 4A 12V DC Output
  • Integrated UPS function VRLA Battery back-up
  • Fire enable
  • Mains failure & Low-battery signalling
  • Low-battery disconnect
  • House and charge 2 x 12Ah VRLA batteries
  • Input either 110V or 230V

DA457-2: 2x 4A 12V DC Output rack-mount power supply with VRLA battery support and monitoring

This range of 19" 3U rack-mountable switched-mode power supplies can accept 110V or 230V and will provide two regulated outputs of 12V DC at up to 4A each.

These units will house and charge up to 2 x 12Ah VRLA batteries and are equipped with two separate DPCO (double-pole change-over) contacts for mains-fail & low-voltage signalling.

Battery low-voltage disconnect, if the voltage from the battery falls below 9.5V DC, for example after an extended mains-failure, the battery terminal will disconnect. When the unit voltage recovers (when mains is resumed) the battery terminals will reconnect, allowing recharge.

Fire enable output switching can be driven from a 12V or 24V DC supply. A typical use for this relay would be interfacing a fire panel with the power supply to de-power magnetic locks in the event of a fire condition.

Integrated UPS function VRLA Battery back-up support

VRLA batteries can be placed within the enclosure and connected to the battery terminals of the PCB. This power supply will automatically float-charge the battery to capacity, providing continuous uninterrupted power from the battery if mains power is unavailable.

Batteries are not included. This unit can be used with or without batteries fitted.

Fire enable

Output switching can be driven from a 12V or 24V DC supply. A typical use for this relay would be interfacing a fire panel with the power supply to de-power magnetic locks in the event of a fire condition.

Mains fail signalling

If the mains-input power is not detected for approximately 30 seconds, the mains-fail relay will change-over. The delay helps prevent false triggering during common power fluctuations within the national grid. The clean normally open-circuit (N/O) & normally-closed-circuit (N/C) relay contacts can be used to switch or signal other systems.

Low-voltage signalling

Should the connected VRLA battery be nearing depletion, the Low Vol relay will change-over. The clean N/O & N/C relay contacts can be used to switch or signal other systems.

Low-battery disconnect

In the event of a prolonged mains power failure where the connected VRLA battery has been depleted, the battery will be automatically disconnected to protect against damage from deep discharging. When mains power is restored, the battery will automatically be re-connected and float-charged ready for use.

House and charge 2 x 12Ah VRLA batteries

The DA457 has an easy access 3U pull out front drawer that can house up to two 12Ah 12V VRLA batteries. Once connected, these will float-charge at 13.7V when mains power is available.

19" 3U rack-mountable enclosure

All-in-one power and UPS, ideal for security and access control applications in one single 19" 3U rack-mount unit.

Removable front plate

The DA457 pull out drawer has a removable front plate to give easy access to the units individually fused outputs.

Input either 110V or 230V

The mains-input can be set with a selector switch in either an 110 or 230 position during installation. The 110 sets the unit to accept a 110V mains-input voltage and the 230 sets the units input to 230V AC.

IEC C13 lead with UK mains plug

This unit is fitted with an IEC C14 socket to accept IEC C13 connectors. Each product includes an IEC lead with a UK Mains plug.

Ordering information

DA420 Variations

Technical information

Download Data sheet

Output

QuantityTwo
Voltage12V DC (13.7V DC)
Current4A
Connection typePCB terminal block (2.5mm²)
Fused20x5mm 4A glass fuse

Mains fail signalling contacts

Contact configurationDouble pole change-over (≈ 30 second delay)
VoltageMaximum 30V DC
Current5A
Connection typePCB terminal block (2.5mm²)

Battery

VRLA Battery deep-cycle protectionYes
Automatic disconnectBattery depleted to 9.5V
Automatic re-connectMains voltage available (Automatic float charging begins)
Fuse protection10A 20x5mm Glass fuse
IncludedNo
Recommended capacityTwo 12Ah 12V VRLA

Battery low-voltage signalling contacts

Contact configuration Double pole change-over
Voltage Maximum 30V DC
Current 5A
Connection type PCB terminal block (2.5mm²)

Input

Voltage Selectable 110V or 230V AC @ 50Hz (+/- 10%)
Power consumption < 143VA
Connection type IEC C14
Fused 6.3A Mains fuse (BS1362)
Mains-on indication Neon lamp

Environmental

Operating temperature -10°C to +40°C
Storage temperature -20°C to +50°C
Operating relative humidityMaximum 95% non-condensing
Ingress protection N/A

Dimensions:

Product

Width480mm (19" Rack-mount)
Height133mm (3U Deep rack-mount 5.25")
Depth480mm
Weight< 9.5Kg
Enclosure materialMild steel
FinishTexture powder-coated black semi-gloss

Ordering information

GTINPart codeDescription
DA457-2 Rack-mount 2x 4A 12V DC PSU with UPS & monitoring

Other models

GTINPart codeDescription
DA457-1 Rack-mount 1x 8A 12V DC PSU with UPS & monitoring
DA457-4 Rack-mount 4x 2A 12V DC PSU with UPS & monitoring
DA457-8 Rack-mount 8x 1A 12V DC PSU with UPS & monitoring
DA457-16 Rack-mount 16x 500mA 12V DC PSU with UPS & monitoring

Available from all good distributors.