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Saturday, April 30, 2011

Update on Low Specific Gravity Lead Acid Batteries

In my last post, I have recommended three action plans for Station Battery monitoring, namely replacement of the battery cells with low specific gravity,formulation of monitoring logbook for electrolyte level for station batteries, and Installation of ACU for Battery Room. So far, Airconditioning System and monitoring and topping-up of electrolyte level were implemented. We cannot replace the affected batteries since there are no spares left. The spare batteries of district one substation were all used when a cell of a battery bank exploded at a particular substation.
Saft Battery Charger Model 125 TPR 150
Therefore, we will resort to constant monitoring of these low affected cells. One solution that we implemented is to increase the float voltage of the rectifier. This can be done by adjusting the potentiometer that controls the level of float voltage. The float voltage of the charger is measured at 128.9 VDC while in the test report of the charger, it is set at 139. 1 VDC. We adjusted the float charge voltage to 133.3 VDC to see if higher float voltage can still reverse the low specific gravity of some station battery cells. We used a precision voltmeter to read the voltage at the battery terminal block. It is also recommended that at least 5% minimum load is connected to the battery.
                                                             Battery Terminal block

The potentiometer for adjusting the float voltage can be found on the bottom part of the control card. The output voltage is affected as turning clockwise will give an increase voltage while turning counter-clockwise will give a decrease voltage. The specific gravity of the affected cells will be monitored for a week and if the results will improve, we will adjust the float voltage to its value as per test report.
The potentiometer at the bottom of the control card

The control cards of the SAFT NIFE Battery Charger


  1. Safety control is important when dealing with these devices.

  2. Dear Sirs,

    Would you please send us best price list and delivery time for the Following Item, to order from your company.

    1. BATTERY CHARGER, A505. PO 110V TPR 50A
    Type Charger : PO 110V TPR 50A
    Reference : 1 ALBA 001 RD
    Code: 66469/01 OR 66974/01
    Power Supply: 460 V OR 480 V
    Battery: 210 AH
    Manufacture: SAFT NIFE
    Quantity: 1 Unit

    Type: SPH 190 (190AH)
    Single Cell: 1,41 -+ 0,01 V/CELL
    Dual Rate: 1,45 -+ 0,01 V/CELL
    Manufacture: SAFT NIFE
    Quantity: 96 CELL

    Spesial Note:
    - Certificate Original Of Manufacture (Mill Certificate)
    - Delivery point: Singapore
    - Please Inform Weight and packaging dimension (estimation), for us calculation freight cost, custom,etc, from Singapore toe Aceh, Indonesia.

    Should you have any question or problem in this inquiry, please do not hesitate to contact me.

    Best Regards

    Erick Tan

    Mahoni No.98 Btn Palda Arun,
    Lhokseumawe, Aceh Indonesia 24354
    Phone: +62 813-77089944
    Fax: +62 645 56698

  3. Hi, I am doing repair job for this exact type unit. Do you have schematic diagram for the control board. I need it to do trouble shooting needs.

  4. In the automotive battery testing industry, the occurrence of false positives or false negatives are widely overlooked. but when it comes to life safety systems, uninterruptible power and mission critical, the story is completely different. https://belltestchamber.com/testing-standard/iec62133


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