BITE3 battery impedance tester

The best frequency for impedance testing depends on the battery type, the site conditions, and previous maintenance practices. The IEEE 11888 standard for VRLA batteries recommends, for example, that a baseline impedance measurement is made six months after the battery has been put into service, and that further impedance measurements are made at quarterly intervals thereafter. For flooded lead-acid batteries, Megger recommends impedance testing at six monthly intervals. Impedance measurements should also be made immediately before carrying out every capacity test.

IEEE Recommended (Maintenance) Practices cover the three main types of batteries: Flooded Lead-acid (IEEE 450), Valve-Regulated Lead-acid (IEEE 1188) and Nickel-Cadmium (IEEE 1106). Generally speaking, maintenance is essential to ensure adequate backup time. There are differing levels of maintenance and varying maintenance intervals depending upon the battery type, site criticality, and site conditions. For example, if a site has an elevated ambient temperature, then the batteries will age more quickly implying more frequent maintenance visits and more frequent battery replacements.

In reality, float voltage measurements are of limited value. They can be used to confirm that the charger is working, but they give no information at all about the battery's state of health. Measuring the float voltage of a cell will also show whether or not it is fully charged, but it is important to remember that, just because a cell is fully charged, this doesn’t mean that it will deliver full capacity. It is by no means unusual for a battery that is close to failure to have a float voltage that is within acceptable limits.

A low float voltage may indicate that there is a short in the cell. In a lead-acid battery, this should be suspected if the float voltage is 2.06 V or less, assuming that the charger is set for 2.17 V per cell. In other cases, a cell may float at a considerably higher voltage than average. This may be because the high float voltage cell is compensating for another weaker cell that is floating low. It is also possible for one cell to float high to compensate for several cells that are floating a little low, because the total of all the cell float voltages must always equal the charger setting.

Yes, the BITE3 is one of the easiest battery impedance testers in the market. With onboard analysis and cell comparison data, you can make a quick and easy evaluation of your battery bank while in the field. With the addition of Power DB LITE software, you can perform more detailed and advanced analysis of your battery bank and individual cells.   

No, there are a variety of battery types and connections therefore the BITE3 has a full line of accessories to meet your testing and connection needs. 

The BITE3 is a small, light  handheld unit that is designed to measure lead-acid batteries of 2000Ah or less. It also has a built-in spectrum analyser and measures DC float current to further evaluate the health of your battery charger. An optional CT is available to measure escape current when your battery system configuration has short strings in parallel. With on board data analysis, you can evaluate the health of your battery and charger in the field. 

Experience shows that loose inter-cell connections that heat up and melt open are responsible for more battery failures than defective cells. This is a particular problem with lead-acid batteries that are frequently cycled, as the negative terminal may cold flow, thereby loosening the connection. Checking intercell connection resistance is, therefore, vitally important. However, it is essential to follow the correct sequence of test when working on multi-post batteries, and also to ensure that the instrument being used employs a method of testing that will provide valid results in this application.