Measuring the charge in your leisure battery To enable you to do this, you will need a digital multimeter. These are not expensive and small simple multimeters can usually be found for around £10 in electronic shops or big DIY stores. Set the multimeter scale to read 20 volts DC. With the 12 volt electrical system turned off, place the red lead on the positive terminal (+ve) and the black lead on the negative terminal (-ve). Read the voltage displayed on the multimeter. To maximise the life of the battery, it is advised you never let the charge drop below 50%. Charge Levels for a lead acid battery Leisure batteries with a voltage of below 11.81 should only be charged with a 4 stage charger otherwise damage to the plates may occur. For the best charging performance when the leisure battery is not in use (over winter) look for a charger that offers a 4 stage charging process ( Bulk – Absorption – Equalisation – Float). For the most accurate results using this method of measuring the state of charge (SOC) the battery should have been rested for at least 6 hours – i.e not been charged or any load put on it. Other factors also determine the SOC, like temperature for example. This is offered as a guide ONLY.