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REF may not be implemented because it is not cost effective - smaller Transformers may be protected by a fuse only, a utility may have standard relays to use at specific voltages that do not include REF, a utility may have had misoperations with REF and feel it is unjustified (instead using a slower ground time overcurrent).
One problem with REF is guarunteeing which way the neutral CT is starred. For CT's on the windings of a transformer, primary current can be pushed in from the windings to verify starring; I don't believe it is a good idea to do this on the neutral. I have set it before but not enabled tripping until a relatively close ground fault occurs on the system where the starring of the neutral can then be verified.
What else can I help you with?
How you using ref relay in transformer?
an REF relay (restricted earth fault) is used to provide ground fault protection for a transformer. Its' operation is limited by CTs starred towards the transformer (usually on the transformer bushings or in breakers used to isolate the transformer), so it will only operate for transformer related faults. Because of this, it can be set to operate very quickly.
Will REF protect the outgoing cables when the Ct's are fitted at the transformer?
REF protection, when installed and set correctly, will protect everything within the CT's. If the CTs are on breakers, then yes, the cables from the transformer to the breakers will be in the zone of protection. If the CTs used are in the bushings of the transformer, then no.
What are the steps involved in doorbell transformer installation?
The steps involved in doorbell transformer installation are: Turn off the power to the doorbell circuit. Locate the existing transformer or install a new one near the electrical panel. Connect the transformer to the power source using electrical wiring. Connect the transformer to the doorbell system using low-voltage wiring. Test the doorbell to ensure it is working properly. Secure the transformer in place and restore power to the circuit.
How can I hook up a doorbell transformer?
To hook up a doorbell transformer, first turn off the power to the area where you will be working. Locate the transformer near your electrical panel. Connect the transformer to a power source using electrical wire, making sure to match the wire colors. Then, connect the transformer to the doorbell system using low-voltage wire. Test the doorbell to ensure it is working properly before turning the power back on.
Is transformer is essential for rectifier?
no transformer is not necessary for rectification today most of power supplies have been made without using transformer in order to reduce weight and size of power supply.for example SMPS(switch mode poqwer supply)
What is the REF 452 plus relay?
resistic earth fault relay install on transformer nutral .
What is meant by the term ideal transformer?
ideal transformer is that which has no power losses.if any transformer transfer power to secondary without power loss then that call a ideal transformer
Is transformer an amplifier?
No. In an amplifier, Power Out > Power in. In a transformer Power Out ~= Power In (minus internal losses). An AC generator is more like an amplifier than a transformer.
What is the difference between power transformer and instrument transformer?
A power transformer is used to provide power (to your home, for example), an instrument transformer is used to measure voltage or current (for metering, for example).
What will happen you f the rated power of transformer is changed?
You cannot 'change' the 'rated power' of a transformer except by changing the transformer for another one. You can, though, operate the transformer below its rated power or, for short periods of time, operate the transformer aboveits rated power.
What is meant by the term transform?
ideal transformer is that which has no power losses.if any transformer transfer power to secondary without power loss then that call a ideal transformer
Why is it using low resistance coils in transformer minimize power loss?
To avoid voltage drop in the coil.
