KEPCO EL Series Electronic Load Operator Manual P/N 243-1295 Firmware Version 3.22 through 3.41 - Manual (Page 41)

SERIES EL 062011
3-7
3.11.6 MASTER/SLAVE OPERATING NOTES/CAUTIONS/WARNINGS
Be sure to read and follow the operating instructions described for a single unit and observe all
Cautions and Warnings. A Master/Slave Load configuration is capable of extremely high power
and extremely high currents, thus suitable precautions should be taken when using the Load.
• Use optimal damping (see PAR. 3.14 for setup instructions to optimize damping set-
tings), otherwise use factory default settings.
• Interconnect UUT and Load with cabling designed to minimize inductance. Remember
that rapidly-changing high-currents combined with inductance produces high-voltage
spikes (spikes that can easily damage equipment including the EL Load).
• To minimize spiking and current surges when using computer-controlled remote opera-
tion, the best sequence is:
1. Select Mode (e.g. MODE CURR).
2. Select very low value set point (e.g. CURR 0.2).
3. Engage Load (INPUT ON).
4. Slew Load to desired operating set point (e.g. CURR 105).
3.11.7 MASTER/SLAVE DISCONNECT
Once units have been operated in a Master/Slave configuration, they must be reconfigured to
restore normal standalone operation. This may be accomplished either from the front panel, or
via a computer interface.
From front panel: Turn power off to all units, then remove all master/slave cables. Power up all
units, wait two minutes, then turn power off and then back on to all units.
From computer interface: At master unit send cal:slavemode 0. After three seconds, send
*RST. Disconnect all master/slave cables and then either send *RST to each unit or cycle power
to each unit off and then back on.
3.12 OPERATION VIA COMPUTER INTERFACE
The computer interface (either USB or RS 232 or optional GPIB) can be used to operate the
load from a remote location using a computer using IEEE 488.2 and SCPI commands. Refer to
Appendices A and B, respectively, for a complete list of applicable commands and queries. The
commands INPut 1 (or ON) or OUTput 1 (or ON) are equivalent to using the LOAD switch on the
front panel to engage the load; the commands INPut 0 (or OFF) or OUTput 0 (or OFF) are used
to disengage the load. Figure 3-1 illustrates the commands used to set the load to operate at
100 Amperes from a 12.5-volt source in the Constant Current mode, engage the load, then dis-
engage the load.
The GPIB interface is a listener and a talker; it can send and receive commands. The factory
default GPIB address is 10; refer to.Appendix B, PAR. B.11 to change it.