Littelfuse, Inc. Industrial Relays 102A2

The 102A2 is a three-phase voltage monitor designed to protect 190-480 V ac, 50/60 Hz motors by detecting harmful power line conditions such as phase reversal, voltage unbalance, and high or low voltage. It features an adjustable trip delay of 2-30 seconds for unbalance and phasing faults, while maintaining a fixed restart delay adjustable from 2 to 300 seconds. The device uses a microcontroller-based circuit for constant monitoring and includes single LED diagnostics with five distinct patterns to indicate fault types. It has a SPDT relay output rated at 10 A at 240 V ac, operates in ambient temperatures from -40 °C to 70 °C, and measures 74.4 mm H × 133.9 mm W × 74.9 mm D. It complies with UL508, CSA 22.2 No. 14, and IEC 60947-6-2 standards.