KEPCO EL Series Electronic Load Operator Manual P/N 243-1295 Firmware Version 3.12 (Unit Rev 2) - Manual (Page 28)

2-10
SERIES EL 070110
Use two wrenches to tighten the 3/8 in. (5/16 in. for Dual models) Bolt/Nut on the bus bars.
these hardware items are brass and could shear if overtightened: recommended maximum
torque is 20 lb-ft for the 3/8 in. hardware, 10 lb-ft for the 5/16 in. hardware used on Dual models.
The small resistance created by a loose joint can cause very destructive heating (e.g., a 1 mil-
liohm joint with a current of 400 Amperes generates 160 watts).
WARNING
Reversing the polarity at the LOAD terminals will cause immediate and
significant damage to the load and UUT!
2.6.2.2 SENSE CONNECTIONS
Remote Sensing terminals (±RS) are provided for connection to the UUT in order to compen-
sate for voltage drops on the power cables connected to the ±LOAD terminals. When remote
sensing is used, the readings shown on the front panel accurately reflect the output of the UUT.
To use remote sensing first remove the local sense jumpers (NOTE: Local sense jumpers can
be fabricated as needed using #18 AWG stranded wire) installed on the ±RS Terminal block.
Then connect wires (#24 AWG or 22 AWG) from +RS to the positive output of the UUT, and from
–RS to the negative output of the UUT. Twisting of sense wires is recommended.
If remote sensing is not used, the pre-installed local sensing jumpers must remain in place as
shown in Figure 2-3. Operating the unit with neither local or remote sensing in place will result in
erroneous readings.
Connect the Series EL Electronic Load to the UUT using cabling appropriate for the current and
voltage drawn during testing. Contact Kepco if assistance is needed in selecting the appropriate
wire size, length and physical configuration. Ensure all connectors are suitable for the currents
and that connections are tight. Connections should be re-checked on a regular basis (see PAR.
2.6) to ensure continued low-resistance connections.
CAUTION:When connecting the load to the UUT be very careful not to accidentally short
the UUT output in the process of connecting the wiring. Best practice is to make the con-
nection to the UUT Positive (+) output connector the last connection.
FIGURE 2-8. LOCAL SENSING JUMPERS
NOTE:
1. LOCAL SENSING SHOWN.
2. FOR REMOTE SENSING, REMOVE JUMPERS
FROM ±RS AND CONNECT ±RS TERMINALS
TO CORRESPONDING ± OUTPUT TERMINALS
AT THE UNIT UNDER TEST.