Battery Discharge Test
Battery Discharge Test
(OP)
I am preparing commissioning procedure for battery discharge test. I have read tech manual from Saft-Nife Battery. During discharge test do I record current and voltage at certain interval ? If so, what is time interval for recording ?
Why dischangre test is required for battry ?
Why dischangre test is required for battry ?






RE: Battery Discharge Test
Yes, you should record voltage (of every cell if possible) and current as a minimum. The time interval is up to you. You should have at least 5 readings during the discharge. 15 or more is much better.
A discharge test will help you determine the condition of the battery. You can determine the total capacity, find bad cells, bad connectors, etc. It is the best (but not definitive) way to know the battery is likely to perform when called upon by the UPS.
RE: Battery Discharge Test
RE: Battery Discharge Test
Per IEEE-450 a new lead-calcium station battery is required to be discharge tested within the first two years after installation, some users require a discharge test immediately upon installation.
The best way to monitor the battery bank during a discharge test is to use a system that is designed to monitor the voltage on each cell and the discharge current during the entire test. The data can easily be graphed and any suspect cell identified (i.e. low cell voltage). The test duration should be the same length as what your system is designed for i.e. if you require a 2 hour back-up capability you would run the test for 2 hours at the manufactures rated value at 2 hours. You also need to determine what your end voltage is, this value is normally 1.75 volts per cell but it can be any value it just depends on the low voltage limit of your loads and what type of battery.
If you do not have access to a recording device to monitor all the cells take cell voltage and current readings every 15 minutes of the first hour and every 30 minutes thereafter.
I am not sure why you would want to take hydrometer readings during a discharge test since the specific gravity value will change throughout the discharge. I guess you could theoretically compare the value between the cells but on a large system chances are the values would be different from cell 1 and the last cell recorded.
RE: Battery Discharge Test
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