1656 & 1657 Battery Element Tester Owner’s Manual
STS Instruments Page 75 of 88
9 Application Notes
This section contains remarks and comments on practical matters that apply to testing battery
elements using high voltage testers like the 1656 and 1657.
1. This unit is solid state High-Voltage Pulse type leakage and breakdown Tester with
digital meters. Essentially, it subjects the battery elements to a high peak voltage that
appears between all plates and across all separators.
2. If everything is normal – if there are no defects in the separators, no runs, trees,
etcetera, the battery element will withstand the test voltage, and the instrument will
register a “normal” quality meter reading.
3. This normal quality meter reading is due to the electrostatic capacity between the
plates, and should not vary except in relation to the moisture content of the separators.
4. If separators are defective, or if for any reason opposite polarity spacing within the
battery element are abnormally close, the high voltage applied will jump this gap, and a
rejection will be indicated.
5. The user best establishes exact test voltage for any particular battery element. It is
suggested that a representative group be checked at successively higher voltages until
the voltage that will reject good assemblies is established. The voltage should then be
“backed off” 200 to 500 volts for routine testing of high quality assemblies, and
somewhat more for lower grade elements.
When a capacitive load (the battery) is coupled to an inductor (internal load of the
tester) the voltage developed across the inductor and the capacitor will be higher at
resonance. The outgoing voltage pulse of the battery tester is composed of an
extremely wide range of frequencies so resonance can occur. The battery’s
capacitance will determine the resonance frequency for a particular battery line. The
firing characteristics of the SCR produce different output wave shapes that affect the
frequency of the output and consequently resonance.
6. The most difficult defects to detect are pinholes and splits or tears in separators. With
present day separators a voltage in the 2000 to 2500 volt range may be required. If
some defects are acceptable, the test voltage can be dropped as low as 1500, and
practically all defects except pinholes, hairline splits, and tears will be detected. Holes in
the insulation are normally detected by arcing. The suggested procedure is to use
sufficient voltage to initiate an arc if the insulation has a hole or is missing. The
insulation will prevent arcing. If there is a hole or the insulation is missing, the tester will
arc across and find the fault (no insulation).
7. Battery elements are sometimes tested in a “formed” (the paste in the lattice is
conductive) or an “un-formed” (the past in the lattice is non-conductive) condition. If
the battery element is un-formed when the test is conducted, faults are much, much
harder to detect because a fault must be located in an area between the conductive
lead lattices of the positive and negative plates. If the fault is located in a non-
conductive area, an arc will generally not occur and the fault will be un-detected.
8. The tester does not determine that an element is reversed in a cell. The tester sees only
the potential between the positive and the negative plate.
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