What does pilot duty mean?
A “Pilot Duty” rating means that this relay is made for a specific highly inductive load, such as controlling the coil of another relay or contactor. Contacts with a “Pilot Duty” rating have passed standardized testing to prove they can reliably control a “Pilot Duty” load.
What is a pilot duty relay used for?
These prewired, general purpose relays can be used for controlling high-voltage appliances with low-voltage signals, such as exhaust fans, vacuums, and motors.
What is the difference between a pilot duty in a line break overload?
The line break overload breaks the power to a motor. A pilot duty overload breaks an auxiliary set of contacts connected in the control circuit.
How does a pilot duty overload relay work?
An overload that opens a set of contacts on high current draw and allows them to close when the current draw has decreased. It usually is a pilot duty device. The device will open a set of contacts on high current draws and allow them to close when the ampere draw returns to normal.
What is a pilot duty motor overload device?
A device that is used to detect a high ampere draw of some electric load and break the controlling circuit, stopping the load. Pilot duty overload. An overload that senses the load of the circuit or power–consuming device and breaks a set of contacts that is isolated from the sensing element.
What is the difference between a contactor and magnetic starter?
A contactor applies voltage to a contactor coil to close the contacts and to supply and interrupt power to the circuit. On the other hand, a starter employs overload relays to protect the motor from load surges by shutting it down to prevent overheating.
Is a contactor coil wire like a load or a switch?
They are wired in circuits exactly like switches and they behave like switches because they are switches. Relay coils are loads; specifically, solenoids.
What are the two major types of thermal overload relays?
What are the two major types of thermal overload relays? Bi-metal strip and solder metaling/pot overloads.
What are different types of pilot schemes?
Pilot schemes can generally be broken into two primary categories. Those categories are directional comparison and phase comparison….Contents:
- Blocking Schemes.
- Unblocking Schemes.
- Overreaching Transfer Trip Schemes.
- Underreaching Transfer Trip Schemes. Direct Underreach. Permissive Underreach.
What is pilot wire?
A wire is connected between the CT which is located at different ends of the protection zone. This wire provides the path for the circulating current produce in an abnormal condition, which is sensed by the relay and therefore is tripped; this wire is known as pilot wire.
What is a pilot duty rating?
Solution/Resolution: A pilot duty rating is a contact rating intended for contacts that control the coil of another relay or contactor.
What is a pilot duty rating on a relay?
A pilot duty rating is a contact rating intended for contacts that control the coil of another relay or contactor. These ratings are applicable when controlling loads like relay coils, contactor coils, solenoids, and other similar inductive loads. Contacts with a pilot duty rating have passed standardized testing…
Why are pilot duty ratings important for contactors?
The highly inductive nature of pilot duty loads is hard on contacts; controlling pilot duty loads using contacts not rated accordingly can cause premature failure and improper contact operation. For more detailed information on applying pilot duty ratings in your application, see How to Apply Pilot Duty Ratings.
How does a standing pilot work on a gas heater?
Standing Pilot. When the pilot light is first lit, usually by a button on the outside of the heater, the thermocouple registers the heat and sends an electrical current to the gas valve. This current keeps the gas valve open and supplying fuel to the pilot light. As long as the thermocouple keeps registering the heat from the pilot light,…