The unit shall be prepared and cond

The unit shall be prepared and conditioned for leakage current measurement as follows:
a) The grounding conductor shall be open at the attachment plug and the test unit shall be
isolated from ground.
b) The sample shall be conditioned in an ambient temperature of 21.1 – 26.7°C (70 – 80°F)
and approximately 50 percent relative humidity for not less than 8 h.
c) The test shall be conducted at the ambient temperature conditions specified by (b).
d) The supply voltage shall be adjusted to the voltage indicated in Table 46.6. These voltages
are nominal for the Rain test of Clause 67, the Condenser fan motor failure test of Clause 58,
and Condenser water failure test of Clause 60.
e) Water-cooled units shall be tested with water flowing through the condenser at a rate
required for operation of the system.



With reference to the measuring circuit in Figure 75.1,
the leakage current test sequence shall be as described in (a) – (d).
If the compressor stalls during sequence B or C due to changing the position of switch S2,
the sequence shall be conducted in its entirety in one position of switch S2 and then repeated
in the second position of switch S2.

a) With switch S1 open, the unit shall be connected to the measuring circuit.
The leakage current shall be measured using both positions of switch S2 and with manually-operated unit switching devices successively placed in each mode (fan only, cooling, heating, and the like).
b) With unit controls set for maximum cooling and maximum fan speed, switch S1 shall be
closed to energize the unit. Within 5 s,
leakage current shall be measured using both positions of switch S2.
Following this and using both positions of switch S2,
manual switching devices shall be operated as quickly as possible through all cooling modes,
but not in the “OFF”position,
to determine the maximum leakage current condition.

c) With switching devices set at the position which causes the highest leakage current,
the unit shall be operated continuously until the measured leakage current stabilizes or decreases. Both positions of switch S2 shall be used.

d) Following (c), switch S1 shall be opened to de-energize the unit.
Measurement of leakage current shall continue,
using both positions of switch S2,
until values stabilize or begin to decrease.