A trackside cabinet works without permanent staff, so a supply or insulation fault must report itself before it stops the signalling equipment. DOLD provides three DIN-rail modules for this: the RN 5897/010 insulation monitor for circuits operated as IT systems, the MK 9300N measuring relay supervising the single- and three-phase supply, and the SK 7817N/200 time relay for switching sequences, delays and control pulses.
The interlocking circuits in the cabinet use the OA 5603/39 PCB relays with forcibly guided contacts, designed to EN 50578 (UIC 736) for railway signalling, and POWERSWITCH solid-state switches for cabinet heaters and loads with high switching frequencies.
The time relay and the insulation monitor have in their datasheets a classification to EN 50155 with vibration and shock resistance to EN 61373; selection requires checking the temperature class against the conditions in the cabinet and the voltage range of the monitored system.
Added to these are the RN 9877 phase monitor without auxiliary voltage, the UG 9400 measuring relay with Modbus RTU for remote reading of the cabinet supply state, and the UG 8851 latching relay, which remembers the contact state after a loss of supply.
