Relay protection tester differential test operation method introduction
Relay protection tester is a new type of intelligent test instrument, it replaces the previous regulator and phase shifter combination of test tools, has a small size, light weight, high precision, easy to operate and so on. Relay protection tester is now widely used in line protection, main transformer differential protection, excitation control and other fields, substation automation has become the mainstream.
At present, the domestic manufacturers of relay protection testers are very simple to operate, cost-effective and very high. Here we take the popular Minko Electric relay protection tester as an example to introduce its differential test operation method in detail:
Relay protection tester interface description:
In the differential test, the device outputs two currents from terminals Ia and Ib, which are mainly used to test the differential relay.
Ia phase as action current Idz, fixed for the base wave, variable amplitude.
Phase Ib is used as braking current Izd, which can be set as DC, fundamental wave, secondary current, and the amplitude of each time can be set.
When doing the ratio braking characteristic of differential relay, set the braking current value at the fundamental wave value of Izd, when doing the DC magnetizing characteristic, set the current value at the DC value, and when doing the second harmonic braking characteristic, set the current value at the second current.
When Izd and Idz output AC, the maximum current is 30A; when Izd output DC, the maximum current is 10A.
Various setting quantities that need to be entered for the relay protection tester:
Idz initial value, change step, phase.
Izd amplitude and phase of each secondary quantity.
Manual change/automatic change
The variables that can be changed in the test are Idz amplitude, phase of Idz.
Open-in quantity: during the test, the contact of the component under test can be connected to any one of the switching input terminals.
Open out: two output nodes, all the way to track the process of the test, in the test press "start" when closed, the test "stop" when disconnected; the other way to track the changes in test data, that is, after the start of the test press the "▲" or "▲" or "▲" or "▲" or "▲" or "▲" or "▲" or "▲". The other way tracks the change of test data, i.e. it is closed when the "▲" or " " button is pressed after the test is started and disconnected when the test is "stopped".
Data recording area: In addition to recording the action time and return time when the protection is in operation and returning, two lines on the other side show the current values of Idz and Izd when the protection is in operation and returning.
After data setting, select "Confirm", the screen will display the relay contact status map, select "Start" that is, start the output for the test, the amount of change in the test can be changed automatically or manually, the test method is similar to the AC test. When the relay contact operates and returns, the test record area on the screen will display the operation time and return time of the relay under test, and the current values of Idz and Izd.