Valcom vp-4024c Service Manual

VSP-VP-4024C

Issue 5

VP-4024C

-24 VOLT DC POWER SUPPLY

INTRODUCTION

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

SPECIFICATIONS

The VP -4024C is a fully regulated -24VDC, 4 Amp power supply.
The primary is protected by a 2 Amp 5x20 mm fuse. 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 ± 2.5 Volts 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. 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.

“WARNING: To reduce the risk of fire or electric shock, do not expose
to rain or moisture.”
“WARNING: Shock hazard – Do Not Open.”
“AVIS: Risque de choc Electrique ne pas Ouvrir.”
“PELIGRO: Corriente Electrica – No Abres.”

CAUTION: For continued protection against risk of fire, replace only

Applications

The VP-4024C is designed to be used with:

• All Valcom page control units that require -

24VDC

• Valcom one-way amplified speaker assemblies

that require -24VDC

• Any application where -24VDC filtered talk

battery is required

with 2A, 125V SLO-BLO type fuse 5x20 mm, UL Listed.

Design Features

• Regulated -24VDC "A" battery

• Two 2 Amp outputs

• Outputs may be connected for one 4 Amp output

• Input fuse protected

• LED indication of operation

• Full current limiting

• Over voltage protection

• Floating output

• Full electronic supply

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CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

CAUTION: To reduce the risk of electric shock,

Do not remove cover.

No user serviceable parts inside.

Refer servicing to qualified service personnel.

This symbol indicates that dangerous
voltage constituting a risk of electric
shock is present within this unit.

This symbol indicates that there are
important operating and maintenance
instructions in the literature accompanying
this unit.

Nominal Specifications

Power Requirements
Input Voltage: 105-120VAC, 60Hz, 150 Watts max
Dimensions: 10.70"H x 6.35"W x 3.75"D
(27.18cm H x 16.13cm W x 9.53cm D)
Weight: 12 lbs. (5.44 kg)
Output Characteristics: -24VDC regulated ±10%
"A" battery
Ripple 10 millivolts RMS max
Two 2 Amp outputs

Environmental

Operating Temperature: 0 to +40° C
Cooling: Free Air Convection
Humidity: 10 to 90% (Non-condensing)

INSTALLATION

Mounting

The VP-4024C is designed for wall mounting only.
The unit should be mounted within seven feet of an
AC receptacle.

Screw mounting plate to wall and position power
supply on mounting plate via the mounting slots.

Precautionary Notes:

Power Connections

Use a cord set consisting of a minimum 18 AWG cord
and grounding type attachment plug rated a minimum
of 15A, 250V. The VP-4024C is provided with a
NEMA 5-15 UL Recognized cord set for North
American use.

Connections

• Connections to Valcom page control units are

shown in Figure 1.

• When using the VP-4024C with Valcom page

equipment, strap either of the "+" outputs to a
reliable ground reference point.

• When installing Valcom one-way amplified horns,

connect the white and black wires of the horn to
the power supply "-" and "+" terminals
respectively.

• Multiple power wire runs may be originated at the

VP-4024C by utilizing a connection block.

• When installing Valcom one-way speakers,

connect the 24VDC and GND terminal s of the
speaker to the "-" and "+" terminals respectively.

• Plug power supply into wall outlet.

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) 563­2000 and ask for Technical Support, or call (540) 767­1555 for Valcom 24-hour Faxback System 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

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TROUBLESHOOTING CHART

Problem

1. No output.

2. Blows fuses.

Solution
a. Verify AC present at receptacle.

b. Check for blown fuse.

a. Verify total equipment power consumption does not exceed 2 Amps on
each -24V output.
b. Disconnect AC while making power connections.

VALCOM LIMITED WARRANTY

Valcom, Inc. warrants its products to be free from defects in materials and workmanship under conditions of normal use and service
for a period of one year from the date of shipment. The obligation under this warranty shall be limited to the replacement, repair or
refund of any such defective device within the warranty period, provided that:

1. inspection by Valcom, Inc. indicates the validity of the claim;

2. the defect is not the result of damage, misuse or negligence after the original shipment;

3. the product has not been altered in any way or repaired by others and that factory sealed units are unopened (A service

4. freight charges for the return of products to Valcom are prepaid;

5. all units ‘out of warranty’ are subject to a service charge. The service charge will cover minor repairs (Major repairs will be

This warranty is in lieu of and excludes all other warranties, expressed or implied, and in no event shall Valcom, Inc. be liable
for any anticipated profits, consequential damages, loss of time or other losses incurred by the buyer in connection with the
purchase, operation or use of the product.

This warranty specifically excludes damage incurred in shipment. In the event a product is received in damaged condition, the
carrier should be notified immediately. Claims for such damage should be filed with the carrier involved in accordance with the
F.O.B. point.

Headquarters: In Canada
Valcom, Inc. CMX Corporation
5614 Hollins Road 35 Van Kirk Drive #11 and 12
Roanoke, VA 24019-5056 Brampton, Ontario L7A 1A5
Phone: [phone] Phone: [phone]
FAX: [phone] FAX: [phone]

charge plus parts and labor will be applied to units defaced or physically damaged);

subject to additional charges for parts and labor).

Bottom View

Typical Page
Control Unit *

A Ground (+)

A Battery (-)

B Ground (+)
B Battery (-)

24V Outputs

-+

-+

VP-4024C
Power Supply

Optional Ground
Reference Strap

FIGURE 1 - CONNECTIONS TO VALCOM PAGE CONTROL UNITS

* The 2000 Series, the V -2920 and the V-2924A Control Units do not require an external power supply. When using
hese units, external power supplies will be connected to ancillary equipment.

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