HVTest HT-802, Руководство пользователя

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2. Test functions introduction
(1) Voltage, current tests
Select a phase voltage or a phase current as variable, select automatic or manual test
changes until the relay actions. When the voltage is more than 125V, current is more than
30A, the voltage can be line voltage output, such as UAB, UBC, and UCA. The current can
output by two phases or three-phase in parallel, note the current phase should be the same
phase. The current output time is as shortest as possible; the initial value can be set to 90%
of the fixed value, in order to shorten the test time. Do multi-stage over-current protection, can
be directly output 1.2 times the setting current, so as measure action time accurately.
(2) Frequency test
The default value of the initial frequency: 50Hz, the user can modify this value. Select
variable frequency input frequency step, click [start test], all current, voltage, frequency
changes.
(3) Power direction test
Protection devices generally use 90 degree wiring, low voltage set 60V, UA = 60V, phase
is 0 degree; UB = 0V, the phase is 0 degrees; Thus, the line voltage UAB = 60V, the phase is
0 degree, and then fix voltage , IC amplitude constant ( generally take it as 5A ) , change the
phase of the IC to measure the boundary angle. 90 degree Wiring takes "UAB, IC", "UBC, IA"
and "UCA, IB" mode as output. 0 degree Wiring takes "UAB, IA", "UBC, IB" and the UCA, IC
“manner as output. The sensitivity angle = (boundary angle + boundary angle 2) / 2.
(3) Transformer composite voltage lockout ( direction) over-current protection
Composite voltage lockout (direction) over-current protection is generally used for
back-up protection of the transformer which can be used [AC test] module to simulate the
operation as follows:
①
Low voltage lockout (direction) over-current protection
Assumptions: low voltage lockout value to be 60V (refers to the line voltage),
over-current setting value 5A. UA , UB , UC , UN ; IA , IB , IC and IN are access to the AC
input terminal of the transformer backup protection , at the same time protect export trip