Sentry Model HM-535 Power Supply
Installation and Service Manual
430-535 0104 © 2004 Heritage MedCall, Inc.
3
4. Batt:
The battery is connected via the screw terminals marked BATT+ and BATT-
Connect these terminals to the Sentry battery with 14AWG wire.
Make sure of correct polarity.
2.3 GROUNDING
The metal power supply enclosure is electrically connected to the AC Ground
terminal for connection to earth ground (AC wiring ground).
For continued protection from lightning damage, the DC output must be
isolated from earth ground.
In other low voltage systems the negative side of the DC voltage is often referred
to as "system ground", however in a Sentry system, the DC negative is "System
Common" and is never to be connected to the building's electrical ground or earth
ground.
Always operate the power supply with the door closed for proper cooling and
protection from electrical shock.
2.4
BATTERY BOX
Refer to the Installation Wiring Diagram on page 12. Install the battery box in close
proximity to the power supply. Mount the box with the door hinge at the bottom or
top. The supplied cable length is 36". Mount the battery box to the wall with screws
or anchors. Note that the battery weighs almost 15 pounds and the box must be
securely mounted.
Route the battery cable to the battery through a knock-out in the box side. Install a
plastic grommet (supplied) to protect the wire. Install the push-on connectors to the
battery after the power supply is operating. Secure the box door with a screw.
3.0
TROUBLE SHOOTING
Check the status indicators.
OUTPUT:
The green OUTPUT LED lights to show the DC output is On.
LPSV:
The Red LPSV LED lights to indicate low power supply voltage.
LOW BATT: Lights to indicate low battery voltage or disconnected battery.
XMIT:
Flashes green to indicate data communication with the console.
CHG TRBL: Lights to indicate the battery charger is not functioning.
IN BACKUP: Lights to indicate when the load is powered from the battery.
During normal operation the OUTPUT LED is On and the XMIT LED will flash.
3.1
POWER SUPPLY
If the LPSV (Low Power Supply Voltage) LED is On, plus the OUTPUT and
BACKUP are Off, the power supply has failed or is shut-down because of overload.
Note that the CHG TRBL LED will always light when the LPSV indicator is On; the
