RS PRO Hydrometer

If you service automotive batteries, this highly precise battery hydrometer for measuring the state of charge of lead acid batteries when servicing automotive batteries is ideal.
Designed for use in the automotive industry, this battery hydrometer offers a fantastic degree of precision when measuring the state of charge of lead acid batteries when servicing automotive batteries. It is the perfect instrument for measuring the specific gravity of battery electrolyte and it allows each cell to be individually checked at a glance. The high precision scale is in Baume degrees & specific weight with coloured sections for a quick reading.

• High-quality glass tube
• Easy reading test results thanks to high-precision scale in Baume degrees and specific weight with coloured sections
• A quick and accurate measure of specific gravity of individual cells of a battery

A hydrometer is a device Designed for use in the automotive industry, this battery hydrometer offers a fantastic degree of precision when measuring the state of charge of lead-acid batteries when servicing automotive batteries.

What is Specific Gravity?

Hydrometers measure the specific gravity of liquids. Specific gravity is the ratio of the density of the liquid being tested to the density of water. In battery testing, the hydrometer is measuring the specific gravity of the battery’s electrolyte. The higher the acid concentration in the electrolyte the higher the specific gravity. Based on the specific gravity you can then tell the state of charge and condition of the battery.

How to read a battery hydrometer?

The typical range of values on the scale is 1.100 to over 1.300. The numbers are specific gravity values or the density of the liquid compared to that of water which has specific gravity designated as 1.000. The typical full–charge reading for an industrial battery is 1.275 (although some may be more so check manufacturers data for the recommended full charge specific gravity reading). A lead–acid battery is ready for recharging when it has reached its 80% discharge point, and this is indicated by a hydrometer reading between approximately 1.140 and 1.180. Battery operation below 1.120 is not recommended.

Handy Tips on using a Hydrometer

• Measure more than one cell when checking for state of charge
• You might not get an accurate reading right after watering the battery
• Battery temperatures affect reading accuracy, electrolyte should be at normal room temperature
• For safety reasons wear eye protection
• Rinse out hydrometer after using as the residue is corrosive