Robertshaw Vibration Monitor 561-WO 117V Allis-Chalmers / 125V DC

The Robertshaw Vibraswitch Monitor Model 561-WO is a supervisory control unit designed to work with Robertshaw Model 365 and 366 Vibraswitch malfunction detectors on rotating and reciprocating machinery. The unit provides start delay and monitor delay functions to filter out transient vibration events during machine startup and short term mechanical disturbances, preventing nuisance shutdowns while preserving alarm response to sustained excessive vibration.

Identified from the manufacturer nameplate as Robertshaw Controls Co., Anaheim Division, Anaheim, California, with serial number 7438463. Supply rating is 117V AC, 50/60 Hz or 125V DC. Power consumption is 110 watts, 120 VA. The unit incorporates DPDT relay contacts rated 115V AC at 6 amp, 230V AC at 3 amp, 125V DC at 1 amp, and 460V AC at 1.5 amp. PCA board marking reads 044 950 244 Rev 2.

Front panel controls include a Start Delay dial calibrated in seconds with positions at 5, 15, 30, 60, 90, 120, 150, 180, 210, and 240, and a Monitor Delay dial calibrated 2 to 30 seconds. A test pushbutton and indicator lamp are mounted on the same panel. Field wiring is terminated at a numbered terminal strip with positions for switched line and continuous line connections, including neutral, hot, and ground. The unit is housed in a painted steel enclosure with knockouts for conduit entry. Internal fuse and spare fuse holders are provided.

Stock # 0526-02281