User manual

2.8 AC Current
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AC Current
Advanced Setup > AC Current
62
The GSC400 controller is designed to measure AC current from the generator
with the use of current transformers (CTs). UCTs with a rating of 5A on the
secondary are required. The maximum allowed current on the GSC400 AC
current terminals is 5A.
Use large AWG wires for runs longer than 5ft. The shunt resistors used for
sensing of current are very low resistance. The accuracy can be affected by
resistance of CT wires.
When Current Transformers (CTs) are operated open circuit they produce
extremely high voltages which can be deadly to personnel. Always disconnect
or disable sources of power when working on CTs. CT shorting bars or blocks
should be installed.
It is extremely important to connect each CT to its proper terminal location.
Never mix A, B, and C phase CTs.
One CT is required for each phase. The wiring for CTs is as follows:
For single phase two wire applications
 CT #1 leads to terminals Phase A+ and A-.
For single phase three wire applications
 CT #1 leads to terminals Phase A+ and A-.
 CT #2 leads to terminals Phase B+ and B-.
For three phase applications
 CT #1 leads to terminals Phase A+ and A-.
 CT #2 leads to terminals Phase B+ and B-.
 CT #3 leads to terminals Phase C+ and C-.
The CTs can be connected in any polarity. The GSC400 measures and displays
the absolute value of the current.
The current transformers (CTs) leads must be terminated individually into the
GSC400 AC Current connector. Do not tie the leads together. See the system
wiring diagram (Figure 4 on page 17) for more details.