GE Industrial Solutions ProTrip Conversion Kits K-225, K-600, K-800, K-1600 User Manual

Page 22

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as indicated in Figure 36. In particular, check the
following:

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a. Verify that the neutral sensor has the same rating

and tap setting as the phase sensors.

b. Verify continuity between the neutral sensor and

its equipment-mounted secondary disconnect
block. Also check for continuity from the breaker-
mounted neutral secondary disconnect block
through to the trip unit wiring harness connector.

c. If the breaker’s lower studs connect to the power

source, then the neutral sensor must have its load
end connected to the source.

d. Verify that the neutral conductor is carrying only

the neutral current associated with the breaker’s
load current (the neutral is not shared with other
loads).

5. If the preceding steps fail to identify the problem,

then measure the sensor resistances. The appro-
priate values are listed in Table 1. Since the phase
and neutral sensors are electrically identical, their
resistances should agree closely.

Breaker

CT Rating, A Resistance, ohms

K-225

150
225

9–12

14–18

K-600

225
600

14–18
40–50

K-800

150
400
800

9–12

27–32
58–79

K-1600

800

1600

58–79

130–154

Table 1. CT resistance values.

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