This document describes a relay with two main coils and one lag coil. A variable resistor or potentiometer connected across the lag coil allows adjustment of the relay's different operating circles. Increasing or decreasing the resistance effectively increases or decreases the contact closing torque of the relay. When the relay is energized with two voltages, a flux is produced that is proportional to the sum of the applied voltages. This flux divides and returns through the outer legs of the electromagnet. The lag coil on the left leg causes the flux in that leg to lag the main pole flux. The out-of-phase fluxes thus produced in the disc gap cause a contact closing torque.
This manual describes the construction, operation principles, and functional blocks of the I.L. 41-681.1R synchro‑verifier relay, including the main and lag coils, restraining element, and optional indicating contactor switches (ICS/ACS). It details the CVE, CVE‑1, CVE‑2 and CVE‑3 relay functions for hot‑line, hot‑bus and synchronism‑check operations.
The document also covers installation requirements, wiring, setting adjustments (time‑dial, operating circle), routine maintenance, calibration procedures, and acceptance checks. Guidance is given for mounting, grounding, contact adjustment, and burden measurements for both AC and DC operation.
| Continuous voltage rating | 110 % of rated voltage |
|---|---|
| Burden (60 Hz) | 15.4 VA |
| Time‑dial setting for 20 s operation | Position 11 gives 20 ± 1 s contact closure |
The relay should be mounted vertically on a switchboard panel using the four mounting holes for semi‑flush mounting or the rear mounting stud for projection mounting, and grounded via the mounting stud or screws.
Set the time‑dial to number 4 or higher when using a 40‑degree circle.
The contact gap should be approximately 0.047 inches between the moving contact and the adjustable stationary contacts.
Each SX unit has a burden of 5.5 W at rated voltage and 1 W at rated current.