Ni-Cd accumulators are used as part of batteries 21, 36, 42, 46KPL-125P for backup power supply of control and lighting systems of electric locomotives VL, ChS.As part of battery 90KPL-55P it's used for backup power supply of control and lighting systems of electric trains ER-2Т, ER-4, ED-2, ED, ER-7, ER-9, EP.