Valcom vp 4024b User Manual

VP-4024B

-24 VOLT DC POWER SUPPLY

INTRODUCTION

These instructions provide the specifications,
installation and maintenance information for the
VP-4024B, -24 Volt Power Supply.

SPECIFICATIONS

The VP-4024B is a fully regulated -24 Vdc 4 amp
power supply. The primary is protected by a circuit
breaker and the two amp outputs by fuses. The
output is floating with respect to ground, and the two
outputs may be connected together for one 4 amp
output. The regulator will maintain -24 volts "2V
over the rated range of input voltages and output
loads. A greater than 4 amp load on power up will
cause the power supply to current limit and the
overload LED will light. Short circuit protection is
provided. Over voltage is provided to limit the
output voltage to approximately -28 volts should a
failure occur within the power supply.

Applications

The VP-4024B is designed to be used with -

VSP-VP-4024B

Issue 6

Nominal Specifications

Power Requirements
Input Voltage: 105-120 Vac, 60 Hz, 150 watts max

1.75 amps
Dimensions: 7.0"H x 9 .5”W x 5.5"D
(17.78cm H x 24.13cm W x 13.97cm D)
Weight: 12 lbs. (5.45 kg)
Output Characteristics: -24 Vdc regulated "2V

"A" battery

Ripple 10 millivolts RMS max.

Two 2 amp outputs

• All Valcom page control units

• Valcom one-way amplified speaker assemblies

• Any application where -24 Vdc filtered talk

battery is required

Design Features

• Regulated -24 volts DC "A" battery

• Two 2 amp fused outputs

• Outputs may be connected for one output total 4

amps at 25 degrees C

• Input circuit breaker protected

• LED indication of output overload

• Full current limiting

• Over voltage protection

• Floating output

• Full electronic supply

INSTALLATION

The VP-4024B is designed to be wall mounted within
7 feet of an AC receptacle. A cold water pipe or
earth ground should be connected to the local ground
screw terminal using 12 AWG or larger ground wire.

Connections

• Connections to Valcom page control units are

shown in Figure 1.

• When using the VP-4024B with Valcom page

equipment, a strap may be added from the local
ground terminal to either of the ground outputs.

• When installing Valcom one-way amplified

horns, connect the white and black wires of the
horn to the power supply -24V and ground
terminals respectively.

• When installing Valcom one-way speakers

connect the -24V and ground terminals of the
speaker to the corresponding power terminals.

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NOTE: Each –24 Vdc screw terminal is fused by a
2 amp WER 2 type fuse. Therefore, when
connecting equipment to this power supply, the load
should be distributed between the (2) 2 amp output
terminals and each load should not exceed 2 amps.

Permanent Installation Instructions

(For use when local codes require conduit to power
supply)

Before beginning this procedure, disconnect power
supply from AC service and customer connections.

A. Connect the AC input green/grounding

conductor and the green ground wire from
the faceplate to the chassis connection for
the ground wiring.

B. Connect the black wire to the circuit breaker

terminal using a .250" tab receptacle.*

C. Connect the white wire to the transformer

terminal using a .250" tab receptacle.*

6. Join faceplate to cabinet; replace the six (6)

screws and lockwashers.

7. Reconnect supply to customer connections,

and return power supply to service.

1. Open cover of supply. Remove the six (6)
screws holding the faceplate to the cabinet.

2. Using pliers, squeeze the strain relief
bushing associated with the AC input cord.
This enables the removal of the power cord
and strain relief bushing from the unit.

3. Separate faceplate from cabinet. Disconnect
the power cord leads from the supply - black
wire from the circuit breaker; white wire
from the transformer; green wire from the
chassis connection.

4. Using a knockout punch (Greenlee #3807 or
equivalent), enlarge the power cord access
hole to 0.875" diameter to accommodate a
1/2" trade side conduit fitting.

5. Install conduit fitting and run the AC input
leads through the fitting. Connect as
follows:

NOTE: The minimum recommended wire
size for AC input leads is 18 AWG; use wire
rated for at least 105 degrees C.

* AMP #42660-2 or an equivalent.

TECHNICAL ASSISTANCE

When trouble is reported, verify the unit is properly
connected and there are no broken connections
leading to this unit.

Assistance in troubleshooting is available from the
factory. When calling, you should have a VOM and a
test set and be calling from the job site. Call (540)
427-3900 and ask for Technical Support, or (540)
427-6000 for Valcom 24-hour Automated Support or
visit our website at http://www.valcom.com.

Valcom equipment is not field repairable. Valcom,
Inc. maintains service facilities in Roanoke, VA.
Should repairs be necessary, attach a tag to the unit
clearly stating company name, address, phone
number, contact person, and the nature of the
problem. Send the unit to:

Valcom, Inc.

Repair and Return Dept.

5614 Hollins Road

Roanoke, VA 24019-5056

Problem Solution

1. No output.

2. Overload LED lights.

3. Blows fuses.

TROUBLESHOOTING CHART

a. Verify AC present at receptacle.
b. Check for blown fuse.
c. Press circuit breaker to reset.

a. Locate and correct short circuit in output wiring.
b. Verify total equipment power consumption does not exceed 4 amps.

a. Verify total equipment power consumption does not exceed 2 amps per
output.
b. Disconnect AC while making p ower connections.

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