The General Electric UR SHB, also cataloged as the SHB Power Supply module, operates as a dedicated hardware component for power conversion and voltage regulation within Multilin Universal Relay (UR) platforms. This module converts field-applied AC or DC input power into the stable, low-voltage DC rails required to drive the internal relay backplane, central processing units, and integrated I/O sub-systems.

Hardware Specifications

Backplane Bus Communication and Power Regulation

The UR SHB integrates directly with the relay chassis to deliver consistent electrical energy to all internal modules via the backplane bus. The module utilizes active regulation circuitry to maintain output stability under varying input load conditions, which is necessary for the precise timing and deterministic operation of the protective logic. Internal diagnostic circuits monitor the health of the output voltage rails, providing real-time status updates to the system controller to ensure immediate detection of power-related degradation.

Frequently Asked Questions

Q: Does the UR SHB support wide-range input voltage operation?

A: The UR SHB is configured for specific input ranges. Consult the module nameplate and the Multilin UR system manual for the nominal voltage and acceptable tolerance range to ensure compatibility with your site’s control power architecture.

Q: Is this power supply module hot-swappable?

A: No. The UR SHB is not designed for live insertion or removal. The host relay chassis must be de-energized to prevent arcing across backplane pins and to protect the internal system logic from transient power-up surges during module installation.

Field Installation Guidelines

1. Confirm that all primary power sources to the Multilin UR chassis are isolated and verified with a voltmeter.
2. Align the UR SHB module with the dedicated power supply slot, ensuring the backplane connector is correctly oriented.
3. Seat the module firmly into the chassis until the rear connector is fully engaged and the front-panel captive screws are tightened.
4. Verify that the primary input power cables are securely terminated at the chassis terminals.
5. Restore power to the unit and monitor the front-panel LEDs to confirm that the power rails are within nominal operating limits.
6. Check the relay’s system diagnostic menu to confirm the internal power health status is reported as normal before assigning the relay to protective service.