Exide Technologies Section 95.10 User Manual

Page 10

7.6 CONNECTION RESISTANCE

Electrical integrity of connections can be objectively established by measuring the
resistance of each connection. These resistances are typically in the microhm range.
Meters are available which determine connection resistance in microhms. Be sure that
the probes are touching only the posts to insure that the contact resistance of connector
to post is included in the reading.

Resistance measurements or microhm measurements should be taken at the time of
installation and annually thereafter. Initial measurements at installation become the
bench mark values and should be recorded for future monitoring of electrical integrity.

It is important that the bench mark value for all similar connections be no greater than
10% or 5 microhms, whichever value is greater over the average. If any connection resis-
tance exceeds the average by more than 10% or 5 microhms, whichever is greater, the
connection should be remade so that an acceptable bench mark value is established.

Bench mark values for connection resistances should also be established for terminal
plates, where used, as well as cable connections. Bench mark values should preferably
be established upon installation.

All bench mark values should be recorded. Annually, all connection resistances should
be remeasured. Any connection which has a resistance value 20% above its bench
mark value should be corrected.

SECTION 8 - INITIAL CHARGE

8.0 CONSTANT VOLTAGE METHOD

Batteries lose some charge during shipment as well as during the period prior to
installation. A battery should be given its initial charge as soon as possible after receipt.

Constant voltage is the only charging method allowed. Most modern chargers are of the
constant voltage type.

Determine the maximum voltage that may be applied to the system equipment. This
voltage, divided by the number of cells connected in series, will establish the maximum
volts per cell (VPC) that may be used.

Table A lists recommended voltages and charge time for the initial charge. Select the
highest voltage the system allows to perform the initial charge in the shortest time
period. Do not exceed the highest voltage listed for a given temperature. Do not exceed
the maximum current(s) shown in Section 9.3.

TABLE A

INITIAL CHARGE

Ambient Temp.

25°C (77°F)

Cell Voltage

2.35

2.40

Time Charge - Hours