Control Relay · Electrical Components & Switchgear
The Siemens 3RB20 and 3RB21 are solid-state overload relays for protecting motors against overload and phase failure. They are mounted with contactors in motor starters in switchboards and control panels. The DNV-listed product type is Overcurrent- and Short-Circuit Relay.
Listed in the DNV Approval Finder at the time we recorded it. The certificate is issued by DNV, not by us; check its current status at DNV.
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