Earthing system IT - Earthing system in which the neutral is isolated from the earth or connected to the earth via a high impedance and the various exposed conductive parts are connected to the earth via individual earthing circuits. An alarm must signal the appearance of a first insulation fault. The installation must be de-energized immediately in the event of a second insulation fault.
Cutoff Voltage (also see End Voltage) - The battery voltage at which the discharge is terminated. The cutoff voltage is specified by the battery manufacturer and is generally a function of discharge rate.
Earthing system TN - Earthing system in which the exposed conductive parts are interconnected and connected to the neutral. The neutral is connected to the earth. The installation must be de-energized immediately in the event of an insulation fault.
IEC (International Electrotechnical Commission) - Advisory organization that draws up international standards in the electrotechnical field.
Voltage-Keyed - A system which incorporates a mechanical identifier on batteries and devices to ensure only batteries of the correct voltage are connected to the device.
Cell - The basic electrochemical unit used to generate or store electrical energy.
Drain - The current withdrawn from a battery during discharge.