NewMar NAV-PAC NP-24 User manual

Model: NP-24
24 Volt
Installation / Operation Manual
General Information
The NAV-PAC protects electronics from voltage spikes, power
surges, momentary power losses, abrupt voltage changes and
noise interference on incoming DC power to MDTs, GPS, and
other onboard Electronics prone to memory loss or “crashes”.
NAV-PAC is a solid state device which provides “pure” power
to navigation electronics by performing several essential
functions.
1) Voltage Spike Protection: Engine cranking, pump and
motor operation send voltage “spikes” through a mobile
electrical system that often “bulldoze” their way through
the electronic circuitry. NAV-PAC eliminates this ruinous
condition.
2) R.F. Noise Filtering: The NEWMAR NAV-PAC contains
a four-element low-pass LC filter which provides very high
radio freqency attenuation in both positive and negative
power leads to the receiver preventing noise from adversely
affecting signal reception and related operation.
3) Back-Up Power: A long-life, completely sealed “Dry Battery”
pack is built-in the NAV-PAC which acts as a power reservoir
and is charged from the onboard 24 Volt power. In the event
of a drop in DC voltage due to engine cranking or total power
interruption, the battery will maintain power to navigation
and communication equipment for a short period of time.
This is essential for preventing memory or data loss.
4) Timed Disconnect Circuit: This circuit prevents damage to
the internal battery from extreme discharge by disconnecting
the NAV-PAC battery approximately 15 minutes after abrupt
drop or complete loss of DC input.
5) Low Battery Disconnect Circuit: This circuit prevents
damage to the internal battery from extreme discharge
by disconnecting the battery whenever battery voltage
reaches 10.2 VDC
Materials Provided
Your NAV-PAC comes with the following materials:
(4) #8 ring lugs for 10-12 guage wire
(1) Installation/Operation Manual
Check to see that these items have been included with the
packaging. For any missing items, please contact factory.
Installation
1) After you have determined the best location in the system,
locate a flat surface close to the power line that feeds the
GPS or MDT. For best results, the NAV-PAC unit should be
within 24” of the critical electronics. The case need not be
grounded, so it is acceptable to mount the unit to wood or
metal. Securely mount the NAV-PAC.
Turn off power to the wires that will be cut or worked on by
disconnecting the battery or shutting off the appropriate
circuit. Identify the positive and negative lead in the power
line and cut at an appropriate location. Use the lugs supplied
to hook up the NAV-PAC to your system.
2) Using the table below, select the proper wire size for your
installation.
AMPS* CABLE LENGTH (feet)
10’ 15’
0 - 10 AMPS 14 AWG 12 AWG
10 - 15 AMPS 12 AWG 10 AWG
*Current draw of equipment being powered.
Replace terminal block cover to prevent accidental shortings
the terminals.
Important Installation Note: If thre is to be a continuous load
on the NAV-PAC output during normal operations, the DC
input must be a minimum of 26.8 VDC to prevent discharge
of the internal battery.

Typical Installation Diagram
Operation
In the event of a loss of DC input to the NAV-PAC, the
navigation equipment is being powered by the NAV-PAC’s
internal battery only. The timed battery disconnect circuit
will initiate. After approximately 15 minutes with no DC
input, the NAV-PAC’s internal battery will automatically
disconnect from the NAV-PAC’s output. This is to protect the
battery discharge if the input is switched off. To reset this
circuit, input to the NAV-PAC must be restored. The timer
will automatically reset once DC input voltage recovers.
Bear in mind that the NAV-PAC has another disconnect
circuit which may cause it to shut down sooner. The battery
is also protected by a low-voltage disconnect circuit. Should
the current draw of teh device being powered cause the
battery voltage to drop to 20.4 VDC before 15 minutes have
passed, then this circuit will disconnect the battery from the
output. The amount of time the equipment will continue to
function normally before the NAV-PAC will shut down will
depend, in this case, upon the current draw of the device
being powered. (See Back-Up Power in the Specifications
section.) To reset this circuit, the internal battery must be
recharged. Reduce or shut off the electronic load, and insure
that an adequate charge voltage is restored to the input.
(See Battery Charging/Replacement).
If you are unable to restore DC power immediately, it is
probably a good idea to turn off the equipment being powered
by the NAV-PAC. Most communication or navigation
equipment with built-in memory has a “keep alive” or “soft”
shutdown that is activated by the on/off switch. But if the
input voltage is slowly reduced, as will occur when the NAV-
PAC battery discharges, this “keep alive” feature may not
activate, resulting in loss of memory, waypoints, etc.
Remember: When you wish to shut off your comm/nav
equipment, you must shut it off with the power switch to
the equipment itself. Do not shut off the input to the NAV-
PAC. The NAV-PAC will simply treat this the same as an
emergency loss of DC input, and will continue to supply
the comm/nav equipment with DC power from its internal
battery until auto-shutdown occurs.
Battery Charging/Replacement
Caution: Do not leave the battery discharged for extended
periods of time. It may be permanently damaged and may
not take a recharge.
The battery requires no maintenance and is completely
sealed. Battery life is up to five years. To charge, the battery
requires an input voltage of 27.6 to 29.6 VDC for 3-4 hours
or more per month. To prevent discharging, the battery
requires a nominal input of 26.8 to 28.8 VDC. These voltages
are normally produced by an engine alternator or good
quality battery charger.
The battery storage time @ 23° C is 400 days. The battery
should be replaced no less frequently than every five (5) years
to guarantee proper operation of the NAV-PAC. (Request
P/N 591-0412-0). The NP-24 uses two (2) 591-0412-0, 12 volt, 5
amp-hour batteries. We recommend replacing both batteries
at the same time.
To determine the age of the battery in your NAV-PAC, check
the quality control sticker on the end of the unit. The first four
digits of the serial number (designated “s/N”) refer to the
year and month of manufacture. For instance, a unit with
a serial number starting “0835” was manufactured the 35th
week of 2008. Be sure to mark the date of replacement on
this sticker for future reference.
Battery Replacement Proceeds as Follows - Refer to Figure
1 & 2
Caution: Take care to ensure that you do not short the
battery terminals during installation. The resulting high
current can melt wires and cause other damage to the unit.
1) Turn off power to the input wiring and disconnect all input
and output connections to the NAV-PAC. Remove the unit
from the mounting surface.
2) Remove the fuse from the fuseholder labeled “BATTERY”
on the front panel.
3) Remove the four screws on the top of the unit and the
foure screws on either side of the unit.
4) Remove the cover.
5) Disconnect the wires from the battery terminals.
6) Remove the four (4) screw/washer sets from the forward
battery braket. Loosen the four screw/washer sets on rear
battery bracket. Slide out the forward battery bracket and
both batteries from beneath the PCB
7) Carefully observing battery terminal location and polarity,
slide the replacement batteries and forward battery bracket
in beneath the PCB.
8) Re-install the four battery bracket screw/washer sets for
the forward battery bracket and securely tighten all eight
(8) battery bracket screws.
9) Re-connect the battery series jumper wire and the -24V
Battery Black and +24V Battery Red to the correct terminals.
Critical 24V Equipmment
(Ground following
manufacturer’s
instructions)
To Other Criti-
cal 24V Loads
DC
INPUT
(Connect to
fused, un-
switched DC
source or one
which is always
powered)
(+)
(-)
Circuit Breakers
(Optional)

10) Re-install cover, fuses, 24 volt output and input connections,
and verify equipment receives 24 volt power.
11) See paragraph 1 of “Test/Troubleshooting” section to
verify back-up power operation.
Dispose of the old batteries properly and according to local
codes. Although the batteries are sealed, they are a lead-
acid type and there maybe restrictions on its disposal.
Test / Troubleshooting
To test the battery operation, disconnect the input power at
the source or remove the input fuse, and, using a voltmeter,
note that the DC output power is still present on the output
terminals. Note that after approximately 15 minutes, the
output will disconnect automatically to protect the internal
battery. You should then measure no voltage on the output
terminals. To reset this timed circuit, reconnect the NAV-PAC
input to the ship/vehicle’s battery.
The noise filtering and spike protection circuitry won’t require
testing unless the NAV-PAC blows fuses repeatedly, or has had
a nearby lightning strike, or other very high energy transient.
If the NAV-PAC blow fuses repeatedly (replace qith 15 Amp
Fast Acting Fuse: ABC-15), this usually indicates a shorted
component. Have a qualified technician perform the repairs
or return the unit to NEWMAR for factory inspection.
Always verify that the replaced fuses are of the correct rating.
Use standard or fast-blow fuses. Do not use slow-blow fuses.
Theory of NAV-PAC Operation
Noise Filter/Voltage Transient Protector with Battery Back-Up
The NAV-PAC is wired in series with the DC power to sensiitive
electronics and:
1) Filters out noise interference on incoming power lines
2) Clamps voltage spikes and transients to a safe level
3) Provides battery back-up power during votlage drops due
to starter motors and momentary losses of power.
Specifications
Input: 24 VDC, Nominal Charging: 27.6-28.8VDC
To Prevent
Discharge: 26.8-28.8 VDC, Maximum 31.0 VDC
Output: Filtered, Voltage Spike Protected with
Back-UP Battery 15 amps max
Back-Up Power: 24 VDC Nominal
5.0 AH Capacity
8 amps for Fifteen (15) Minutes
12 amps for Eight (8) Minutes
15 amps for Two (2) Minutes
Battery: Sealed Rechargeable Lead-Acid 5.0 AH,
5 Years
Typical Life - Replaceable
Filtering: Audio Through 200 MHz
Voltage Spike Protection:
Transient Energy Capability; 100 Joules,
4,000 amps Max.
Operating Temperature:
0-50° C
Size/Weight: 6” H x 6.75” W x 7.5” D; 8 Lbs.
13.3 H x 17.14 W x 19 D (cm); 3.6 Kgs.
Series Jumper Wire
Bracket with
Insulator Pads
+24V Battery RED
-24v Battery BLACK
5) Remove Batteries
4) Slide bracket forward along
battery then pull up
1) Disconnect battery
terminals
3) Loosen rear bracket screws
2) Remove front bracket screws
Figure 1 & 2: Battery Replacement
Procedure
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