Cut Sheet

DESCRIPTION
This variable-purpose power supply is suitable for many differ-
ent applications for security, access control and CCTV system
accessories that need supplementary power. NP-P3A power
supply/charger converts low voltage AC input into 6VDC,
12VDC or 24VDC @ 3 amps of continuous supply current (see
specifications).
FEATURES
• Dip switch selectable 6VDC-12VDC-24VDC output.
• 3 amps continuous supply current at 6VDC-12VDC-24VDC*.
• Filtered and electronically regulated output.
• Built-in charger for sealed lead acid or gel type batteries.
• Maximum charge current 350mA.
• Automatic switch over to stand-by battery
• Battery short circuit protection (circuit breaker).
• Thermal overload and short circuit protection.
• AC input and DC output LED indicators.
• Extremely compact design.
• Includes battery leads.
Board dimensions: 99.6mm L x 76.45mm W x 60mm H
* Specified at 25° C ambient.
INSTALLATION INSTRUCTIONS
The NP-P3A should be installed in accordance with The Na-
tional Electrical Code and all applicable Local Regulations.
1. Mount the NP-P3A in desired location/enclosure.
2. Set DC output voltage with dip switches (refer to Voltage Output/
Transformer Selection Table).
3. Connect proper transformer to terminals marked [AC]. (Refer to
Voltage Output/Transformer Selection Table) Use 18 AWG or
larger for all power connections (Battery, DC output).
Keep power limited wiring separate from non-power limited
wiring (115VAC / 60Hz Input, Battery Wires). Minimum .25"
spacing must be provided.
4. Connect devices to be powered to terminals marked [+ DC -].
Note: It is important to measure output voltage before connecting
devices. This helps avoid potential damage.
5. When the use of stand-by batteries are desired, they must be
lead acid or gel type. Connect battery to terminals marked [+
BAT -] on the unit (battery leads included). Use two (2)
12VDC batteries connected in series for 24VDC operation.
Note: When batteries are not used, a loss of AC will result in the
loss of output voltage.
R
333 Bayview Avenue
Amityville, New York 11701
For Sales and Repairs, [phone]
For Technical Service, [phone]
NP-P3A
3 AMP POWER SUPPLY / CHARGER
WI1326D 12/05
© NAPCO 2005
Red
(DC)
Green
(AC)
Power Supply Status
ON ON Normal operating condition.
ON OFF Loss of AC, Stand-by battery supplying power.
OFF ON No DC output. Short circuit or thermal overload condition.
OFF OFF No DC output. Loss of AC. Discharged or no battery.
LED DIAGNOSTICS
Output
Voltage
Dip Switch
Position
Transformer /
Output Rating
6VDC @ 3 amps continu-
ous supply current
1. OFF
2. OFF
P-TRF1650
12VDC @ 3 amps continu-
ous supply current
1. ON
2. OFF
P-TRF24100
24VDC @ 3 amps continu-
ous supply current
1. ON
2. ON
P-TRF28100
VOLTAGE OUTPUT/TRANSFORMER SELECTION TABLE
Terminal
Legend
Function/Description
AC Low voltage AC input (see Voltage Output/Transformer Selection Table).
For 6VDC output use 16VAC or higher with 50VA power rating or higher.
For 12VDC output use 24VAC or higher with 100VA power rating or higher.
For 24VDC output use 28VAC with 100VA power rating or higher.
Caution: Do not apply voltages above 28 VAC (28 VAC is maximum input rating)
+ BAT -- Stand-by battery connections. Maximum charge rate 350mA.
+ DC -- 6VDC-12VDC-24VDC @ 3 amps continuous supply current.
TERMINAL IDENTIFICATION
Item Description Dimension Volume Memo
1 Instruction Sheet 120*80 1
2 Wire 18AWG 22cm 1 Red
3 Wire 18AWG 22cm 1 Black
4 Double Stick Foam Tape 60*20*7mm 1
APPENDIX LIST
AC