Battery element testers have been used for many years in the production of lead-acid battery as they can detect latent plate separator insulation problems before they are shipped. This prevents potential early failures in batteries and avoids customer disappointment with battery quality down the road. These tester instruments are based on surge voltage testing to ensure insulator faults are detected while at the same time preventing any other damage to the plates and separators by inserting very little actual energy despite the high voltage test levels.
Typical test levels used are from 1500Vpk to 2000Vpk but these testers can provide up to 3000Vpk of output if needed. The test method relies on an internal coil which is placed in parallel with the plates and forms a resonant circuit. When the voltage surge is applied to the battery cell, the reflected energy in this resonant circuit results in a series of decaying pulses that are digitized and measured by the tester. A good battery cell will have a consistent reflected amplitude for a given test voltage. Cells with defects however will return different reflected amplitudes which the tester detects by comparing it to the upper and lower acceptance limits programmed.
Operator convenience is greatly enhanced on the new testers by the use of a large color display with large read-outs that are easy to see and the use of color to indicate pass (green) or fail (red) conditions. The front panel has also been improved by using large, easy to reach and see buttons for easy operator access. Up to ten setups can be stored in non-volatile memory now for quick change overs as needed. Setups include a range of programmable parameters like test voltage, upper and lower pass/fail limits, test interval time (repetition rate) and the number of tests to run per cell. A loud buzzer goes off if a fault is detected alerting the operator.
The front panel of both the bench top model and 19” rack mount model can be seen in the photo below. (Figure 2).
Figure 2: Model 1656 Digital Battery Element Tester
The digital design not only improves the number of available test modes, it also provides more accuracy and repeatable results for improved quality testing. Convection cooling with no fan operation keeps dust and dirt out of the instruments interior to ensure a longer life span. An automatic calibration reminder pops up before the annual calibration interval expires to ensure the instrument remains in calibration per ISO9100.
The new STS Instruments 1656 and 1657 tester are costs less than the previous generator analog tester despite their many benefits.