Danfoss AM-PBU 25 Data sheet

Data sheet

AM-PBU 25 Electronic Power

Backup for 24VAC Actuators

AM-PBU 25 is a standby mains power backup

unit for AME 85 or AME 55 actuators. It is used
as an “Electronic Spring Return” unit. During a
power failure an actuator can be powered to its
open or closed position. Normal control of the
actuator automatically resumes when power
returns. The charger section of the AM-PBU 25
keeps the battery in peak condition at all times.
The battery can be monitored remotely from a
building management system (BMS) or volt
meter.

The AM-PBU 25 can serve one AME 85 actuator
or two AME 55 actuators.

Ordering &
Technical Data:

Operation: During normal operation 24 VAC power passes through normally open relay contacts

AM-PBU 25 Code No.: 082H7090
Power requirement 24 Vac / 40 VA
Power output 24 Vac / 25 VA, 2 spdt contacts
Output cycle time 6.5 minutes
Battery 12 V, 1.2 Ah
Ambient temperature
Ambient humidity max. 65 % RH
Enclosure rating NEMA 1 (IP 00)
Standards Emission EN 50081-1

Weight 0.67lb (0.3 kg)
Dimensions 7.5x5.0x1.9in (190 x 127 x 50mm) - panel mounted

in the AM-PBU 25 to the power input terminals on the actuators. In the event of a
power failure the AM-PBU 25 starts to provide 24Vac power to the actuator from the
frequency converter.

14…122°F (-10...50 °C)

Immunity - EN 50082-1
Heat - IEC 68-2-2

This drives the valve either open or closed depending on the wiring of the actuator. The
power backup cycle lasts for 6.5 minutes. Normal operation is resumed when power is
restored.

The condition of the battery can be monitored with terminals TG and BT connected to a
volt meter or Building Management System (BMS).

VD.HU.D1.22©Danfoss 2/2012

1

Data sheet

AM-PBU 25 Electronic Power

Backup for 24VAC Actuators

Electrical Wiring:

The jumper between LN & RC can be replaced by a connection to a building
management system (BMS), a controller, or a manual switch. When the contact opens,
the building mains power is disconnected and the AM-PBU 25 goes through a cycle,
running on battery power. This feature can be used for remote control of the valve or for
testing the battery. Connecting terminals TG and BT to a BMS or volt meter and taking a
reading during an exercise cycle, gives a good indication of battery condition.
Connecting NC1 or NC2 to terminal 3 on the actuator drives the valve stem down on
power failure; connecting NC1 or NC2 to terminal 2 drives the valve stem up on power
failure.

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respective companies. Danfoss and Danfoss logotype are trademarks of Danfoss A/S. All right reserved.

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Danfoss Inc. Danfoss Inc.
Mississauga, ON CANADA Baltimore, MD USA
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VD.HU.D1.22©Danfoss 2/2012