Bird 4421 RF Power Meter
40
Replacing Batteries
1. Disconnect the AC power cord from the ac mains supply.
2. Remove the four screws that secure the top cover.
3. Lift the top cover to access the attached ground wire then disconnect the
ground wire and remove the cover.
4. Unfasten the battery retaining belts then remove the battery tubes
(Figure 19). Be sure to note the polarity and orientation of the battery
tubes before removing them.
5. Remove the batteries from each tube and insert replacement batteries. Be
sure to note the polarity (positive and negative) arrangement of the batteries.
6. Install the battery tubes into the unit and secure with the retaining belts.
Be sure to position the retaining belts as they were before removal and
tighten them securely.
7. Connect the ground wire to the top cover.
8. Install the top cover and secure it with the four screws removed earlier.
Figure 19 Batteries
Long Term Storage
Do not store the instrument for long periods of time without recharging the bat-
teries. When the instrument is stored for long periods of time without use, the
batteries will loose their charge and also loose the ability to reach full charge
when put into service. To restore the battery charge, perform a full charge for 28
hours. If the batteries are not fully charged after 28 hours, completely discharge
the batteries then perform a full charge again. If necessary, repeat this dis-
charge and charge cycle up to three times. If the batteries do not remain
charged after three discharge-charge cycles, replace the batteries.
WARNING
Exposed AC line voltage (115 VAC or 230 VAC). Disconnect the power cord
from the AC line before replacing the batteries. Failure to comply may
result in severe electrical shock or death.
WARNING
Use only Nickel Metal Hydride (NiMH) batteries that have a minimum
capacity of 4500 milliamper hours (mAh). Do not install batteries that are
not Nickel Metal Hydride. Do not install NiMH batteries that have less than
4500 mAh capacity. Failure to comply may result in damage to the batteries,
damage to the instrument, and injury to personnel from battery chemicals.
Item
Description
1
Battery retaining belt
2
Battery tube (batteries inside)
X4
X4