PRIMARY AND SECONDARY INJECTION TEST SETS
Primary and second injection test are used to test a circuit breaker and its protective relays and devices. In the video below, Steve Spohnholz, Senior Electrical Systems Coordinator at Transworld Electric shares which test set best fits your circuit breaker testing needs and how both primary and secondary current injection tests are conducted to monitor the operation of a circuit breaker.
If you have any electrical or circuit breaker testing needs, schedule an appointment with Transworld Electric.
PRIMARY AND SECONDARY INJECTION TEST SETS
Primary and second injection test are used to test a circuit breaker and its protective relays and devices. In the video above, Steve Spohnholz, Senior Electrical Systems Coordinator at Transworld Electric shares which test set best fits your circuit breaker testing needs and how both primary and secondary current injection tests are conducted to monitor the operation of a circuit breaker.
Below Transworld Electric has shared five commonly asked questions about primary and secondary injection test.
- Why do we use Primary & Secondary injection test sets?
One of the reasons is to protect personnel. If the breaker does not trip within its calculated trip time, it could cause a longer trip time and cause an arc flash damage to personnel and extended collateral damage to assets. Another reason is to protect the equipment. If the breaker does not trip within its calculated trip time, equipment downstream could be damaged more than expected.
- What is the purpose of Primary & Secondary injection test set?
The purpose of primary and secondary injection tests sets is to test the trip functions of breakers according to whether they are magnetic, thermal magnetic or digital. The different functions that are tested on the circuit breaker would be a long time and short time which are your overcurrent protection functions, instantaneous which is your short circuit protection, and your ground fault function which is your ground-fault current protection.
- What is the difference between Primary & Secondary injection test?
A primary injection test set injects a multiple of the fault rated current of the breaker, through the breaker while measuring the trip time. The secondary injection test injects a ratio of the fault rated current of the breaker directly into the trip unit and measures how long it takes the breaker to trip. Another way to look at this is a primary injection test tests the breaker as close to a real-world scenario as you can while secondary injection tests the timing and function of the trip unit.
- How do Primary & Secondary injection test sets work?
Primary and secondary injection test work basically the same way, by injecting a calculated amount of current through the breaker and measure how long it takes for the breaker to trip. Each calculated amount of current is different for each type of function you want to test. They all have to be done on each phase, of each breaker, for each function of the breaker.
- What are the different types of injection test sets?
Primary injection test sets are specific to the size and current output, where secondary injection tests are brand specific to the breaker or trip unit.
