8
Rev.12/31/97
C. Recommended Method For Taking Annual Micro-Ohmmeter Readings Across Battery
C. Recommended Method For Taking Annual Micro-Ohmmeter Readings Across Battery
Connections
Connections
Connections
Figure 2. - Placement of meter probes for connection resistance measurements.
Caution:
Never place probes across a cell or cells (between positive and
negative posts), with the meter set on ohms. The meter may be destroyed
and arcing may occur at the battery.
1. Make sure the battery is on float charge before beginning the readings.
Obtain an accurate digital micro-ohmmeter, and set it to the lowest scale.
2. On cell No. 1 take the first reading between the connector lug and the
first post (see fig. 2). This reading will be the resistance between the
post and connector lug and will be about one-half the middle readings.
Record all readings on form POM-134A.
post and connector lug and will be about one-half the middle readings.
Record all readings on form POM-134A.
3. Take the second reading between
opposite polarity posts (not connectors) of
cells No. 1 and No. 2. Following readings will be between positive and
negative
negative
posts
of adjacent cells. These middle readings will include the
resistance of two connections (one on each post) and the intercell
lead(see fig. 2). These readings will be about double the first and last.
lead(see fig. 2). These readings will be about double the first and last.
4. Take the remaining middle readings as in step 4, proceeding from cell to
cell.
5. Take the last reading between the last post on the last cell and the
connector lug as shown.
6. If high resistance is found, take readings from each post to its connector
to determine which of the two connections is bad. Mark this and all
high-resistance connections for later repair.
high-resistance connections for later repair.
7. After readings are complete, disconnect the charger and loads from the
battery.
Caution: do not remove or make connections while current is flowing.
Clean problem connections, retorque to manufacturer's specifications,
and apply no-ox grease. Retest the repaired connections and record the
resistance in the "as-left" column on form POM-134A.
and apply no-ox grease. Retest the repaired connections and record the
resistance in the "as-left" column on form POM-134A.