EFJohnson 7780 Battery Pack and Charger Information, Power Setting Operating Time, Rapid Charger

BATTERY PACK AND CHARGER INFORMATION

SECTION 5 BATTERY PACK AND CHARGER INFORMATION

5.1 BATTERY PACK

CAUTION

Dispose of these batteries in accordance with local reg- ulations. Do not dispose in a land fill. Do not incinerate because an explosion may result.

5.1.1 GENERAL

Standard 1400 mAH Battery Pack, Part Number 587-8150-135, contains six size AA nickel metal- hydride (Ni-MH) batteries connected in series. Also inside the pack are a diode, thermistor, and thermal circuit breaker. The diode protects against reverse polarity when charging and also prevents discharge of the battery through the charger. The thermistor is used by the rapid charger to sense battery temperature.

Intrinsically Safe 1400 mAH Battery Pack, Part Number 587-8150-136, is similar to the standard pack except that it has a thermal fuse and series resistors connected to the negative terminal of the battery. This resistor limits current if a short circuit occurs.

The battery pack is a sealed unit that is not intended to be serviced. If the pack fails to hold a charge or is defective for some other reason, it must be replaced with a new unit. The batteries in this pack have a nominal capacity of 1400 mAH. Typical oper- ating time before recharge is as follows. This assumes that the transceiver is in the standby mode (receive, audio squelched) 90% of the time, the receive mode (receive, rated audio out) 5% of the time, and the transmit mode 5% of the time.

Power Setting	Operating Time
1 watt	8.6 hours
3 watts	7.5 hours

5.1.2 BATTERY CARE

•Repeated deep discharge. Recharging should take place soon after the low battery indication appears. This indication appears when the battery pack voltage drops to 6.3 volts which is approximately

1 volt per cell. Do not regularly continue operating the transceiver until it is completely nonfunctional.

•Regularly recharging a battery after only light use. This may result in shortened operating time. If this has caused shortened operating time, it may be possible to restore it to normal by performing three complete discharge/charge cycles.

•Frequent use at temperature extremes. Maximum battery life is achieved if the ambient temperature when using or recharging a battery is 68-86° F (20- 30° C). The recommended temperature ranges for the various battery functions are as follows.

Function	Fahrenheit	Celsius
Charging	+50 to +104°	+10 to +40°
Actual Use	+14 to +140°	–10 to +60°
Storage	–22 to +122°	–30 to +50°

•Regularly leaving fully charged battery packs in the charger for extended periods (such as longer than over a weekend).

•A short circuit condition that causes overheating that could vent hydrogen and reduce life.

5.2 RAPID CHARGER

The single-unit rapid charger that is used to charge this battery pack is listed in Table 1-1. Also required is either the 117 or 220 VAC power supply. The pack can be charged while attached to the trans- ceiver; however, charge time may be slightly longer. Typical charge time is as follows. This assumes that the battery is discharged to the point where the low battery indication appears.

Typical Battery Charge Time = 1 hour

With proper care, a battery pack should provide many months of service. Some causes of shortened battery life are as follows:

This charger uses state-of-the-art ΔT/Δt (change in temperature/change in time) and – ΔV (negative

	November 1999
5-1	Part No. 001-7780-500