CR100 cyclic interrupter

CR100 cyclic interrupter: overview

The CR100 is a very easy-to-use interrupter for taking On/Off measurements on structures with a single cathodic protection rectifier. Compact, it fits in the technician's toolbox. Its dry contact causes no voltage drop, unlike electronic relays, which also makes it usable on galvanic anodes.

It offers three switching cycles: 4 s (3 s On / 1 s Off), 15 s (12 s On / 3 s Off) and 30 s (27 s On / 3 s Off), with a breaking capacity of 20 A at 60 V. For higher currents (50 to 200 A) and GPS synchronisation, IPSI Solutions offers other cyclic interrupters.

Why interrupt the current during measurement

A potential measured while the rectifier is delivering current includes a voltage drop in the soil that makes it look more negative than it is. To check the protection criterion, the potential is measured just after the current is switched off: the OFF potential. The CR100 performs these interruptions cyclically and regularly, so both values can be read in turn.

CR100 or GPS interrupter?

The CR100 is sufficient when a single rectifier feeds the structure. With several, all sources must be switched at the same instant, otherwise the reading is distorted by those still delivering current: GPS-synchronised interrupters are then required, as they are for currents above 20 A.

CR100 cyclic interrupter: technical specifications

CR100 cyclic interrupter: documentation