Tag: UR8FH

General Electric Multilin’s UR-8FH is a CT/VT module designed to be installed in the general purpose relay family. It provides the relay with 3-1A/5A phase current transformer, 1A/5A ground current transformer and four voltage transformer terminals. Current transformers and voltage transformers are able to reduce current and voltage to manageable levels for relay monitoring and control, and are necessary to generate important data for relays.

CT/VT modules can use voltage or contact inputs on channels 1 to 4 inclusive or channels 5 to 8 inclusive. The UR manual provides more information on proper relay connections, pointing out important details such as how channels 1 and 5 are connected to phase A, and channels 2 and 6 are connected equally to B. The manual also provides the user with full warnings and notifications, for example, for relay terminals with nominal currents of 1 A or 5 A, connections to the CT must match the secondary rating of the connected CT lest the user wish to cause system damage. In summary, before starting Relay connection, users must read the Universal Relay manual carefully.

Frequently Asked Questions about UR-8FH
Does the UR-8FH protect against ground failure situations when integrated into GE Multilin universal relay systems?
The UR-8FH is described as a CT/VT with standard 4CT/4VT. It has no sensitive grounding function, so it can protect universal relays on ground systems classified as high impedance. The modules with this capability are UR-8G, UR-8J, UR-8M, and UR-8R ordering numbers. These references are newer CT/VT generation. There are also two older CT/VT modules (UR-8B and UR-8D) with sensitive ground fault protection. For example, standard models with 4CT/4VT capabilities do have typical capacities of up to 24 analog current transformers and voltage transformers, as described in all CT/VT modules included in various general-purpose relays. In addition to CT/VT modules, universal relays are equipped with sensor I/O modules. This provides the UR with a DCmA card or RTD to monitor flow, wind speed, temperature, vibration, or pressure. The analog output can also be used to connect the UR to an external PLC or other user interface device. The universal relay also features a digital I/O module containing up to 96 contact inputs and 64 contact outputs.