LS3300 Detected a Voltage Overload with error message

​LS3300 Detected a Voltage Overload
(SMU such as GSxxx behave the same way)

LS3300 Detected a Voltage Overload
There are a few factors that we need to consider:
1.    The Yokogawa YCA LS-3300 does have a maximum current output of 62.5 A. However, this maximum current output is not available for just any load.
a.    The available current is limited by the voltage drop across the resistance or lead wire.
b.    This voltage maximum is known as the compliance voltage. The approximate compliance voltage for the LS-3300 ranges are:
i.    100mA and 1A Ranges: 0 to 1.25 A Output Current, 15V Maximum Output
ii.    10A Range: 0 to 12.5 A Output Current, 3V Maximum Output
iii.    50A Ranges: 0 to 62.5 A Output Current, 600 mV Maximum Output
2.    If one rap around the CT is about 8 inches, the 40 raps would equate to about 320 inches of length. Add to this the 3 plus feet of lead wire and you have a total wire length of about 30 feet.
3.    You indicated that you were using 12 gauge housing wire. This wire has a resistance of about 5.21 Ώ per 1000 feet. This equates to a resistance of 0.156 Ώ.
4.    8A dropped across 0.156Ώ = 1.248 V or twice the compliance voltage specification.
5.    Other factors to consider:
a.    #12 wire in a jacket is rated at 9.3A
b.    #12 wire in Air is rated at 41 A
c.    # 4 wire in a jacket is rated at 60A and 0.25 Ώ/ 1000 feet or 75 mΏ; 60 mV at 8 A and 470mV at 62.5A
6.    Also consider shortening the test duration. The current through the wire will raise its resistance. Check the self-heating thermal stability by monitoring the Ct output or the voltage stability at the input of the wire coil.

In summary, order a 4 gauge or larger, extra flexible, jacketed cable. Keep the lead length to a minimum, make low resistance connections to the LS-3300 perhaps through a lug connector soldered to the coil lead wire.