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with cable communication cable, and set the instrument host as cable test mode, after the
success of communication, wireless communication channel of instrument host will
automatically set to the channelvalue consistent with that of voltage collector. Then the test
can be conducted under the wireless test mode.
8. Test Wiring
8.1 Notes
8.1.1
Before testing, the instrument host and voltage collector should be reliable grounded (the host is
grounded by the black clamp of the current test wire).
8.1.2
Current sampling:For single phase test, the current sampling should be input from phase A
channel of the instrument host;and for the three-phase test, the current should be input from
phase A, B and C respectively. The instrument can only use low voltage and small current for
signal sampling, so the test wire should be away from high voltage.
Tip: Take the current from the zinc oxide arrester counter. When the test clamping is
well connected, the counter ammeter pointer points to zero. If the pointer of the
current meter does not point to zero, it indicates that the test folder is not well
connected. At this moment, use the test clamp to rub the connecting part for
several times so that the ammeter pointer would point to zero.
In order to ensure the safety of the test, the black clamp should be connected first,
so that the instrument host is grounded first, and then the other color test clamps
are connected.
8.1.3
Reference voltage sampling: For single phase test, the current is input from the voltage collector
phase A (yellow) channel; and for the three-phase test, the current is input from phases A, B
and C (yellow, green, red). The voltage test wire is connected with 120mA self-recovery
insurance in series to prevent the short-circuit of the test wire, which will cause the secondary
side fault of the PT.
8.1.4
Induction test mode: The sensor plate must be placed on the base of phase B zinc oxide
arrester,the current must be input from the reference signal channel of the instrument host; and
the induction plate must be placed perpendicular to the phase B zinc oxide arrester and its
horizontal position should be on the center wire of the horizontal symmetry of phase A and C.
8.1.5
Wireless test mode: the voltage collector should be placed in a relatively higher position (for
