KEPCO KLP Series User Manual, Rev 4 - Manual (Page 52)

3-10
KLP091313
3 to the OFF (up) position; at next power-up, the stored value buffer is cleared and setpoints will
default to zero volts and minimum current.
NOTE: If the virtual model for the power supply is altered, the last settings are reset to zero
volts and minimum current. Last output state (ON or OFF) is not retained; upon restart
the unit defaults to setpoint mode. See AUTOmatic fault recovery mode (PAR.
3.2.17.3.2.
3.2.11 VIEWING/CHANGING OVERVOLTAGE OR OVERCURRENT PROTECTION VALUES
Overvoltage and Overcurrent protection values can be individually programmed. The range for
overvoltage and overcurrent values are 0.2 to 1.2 x E
O
max and 0.72 to 1.2 x I
O
max. If the output
voltage/current exceeds the overvoltage/overcurrent protection value, the protection circuit
latches the output off, flashes an overvoltage (OVP) or overcurrent (OCP) protection error mes-
sage on the status display and sets a status bit that can be retrieved through the RS 232, GPIB
or LAN port. The unit must be cycled on and off to restore the output. If the internal relay is pro-
grammed to FAULT mode (see PAR. 3.2.17.1), the N.O. and N.C. contacts of the relay provide
status flags via the Analog I/O port connector. The maximum values are 1.2 x E
O
max for over-
voltage protection, and 1.2 x I
O
max for overcurrent protection.
A built-in feature prevents the unit from encroaching upon the above margins for OVP and OCP.
For example, if OVP and OCP are set to 12V and 72A, respectively, programming of the output
is automatically limited to 10V and 60A.
NOTE: When a virtual model is defined (PAR. 3.2.9), OVP and OCP are automatically set 20%
and 20%, respectively, above the maximum programmable values established by the
virtual model. If OVP or OCP are lowered by the user, valid settings will actually be
lower than the virtual model limits because values within 20% guard band of OVP or
OCP are prohibited.
The OVP and/or OCP limits can be changed as follows:
1. Using a thin tool (e.g., end of paper clip), press and hold the PROTECT switch. The output is
switched off, setting voltage to zero Volts, and current to a minimal value, and the status dis-
play shows PROT. The DC VOLTS and DC AMPERES displays show the corresponding
overvoltage and overcurrent protection setpoints while the PROTECT switch is held in.
2. To change the values, operate the corresponding adjustment control while holding the PRO-
TECT switch in. When the PROTECT switch is released, the protection values showing in
the DC VOLTS and DC AMPERES displays are entered as the new protection values.
3.2.12 CHANGING GPIB ADDRESS
KLP supports GPIB addresses from 1 to 30; the factory default GPIB address is 6. To change
the address from the front panel proceed as follows:
1. If the status display shows SET, tap either the CURRENT or VOLTAGE controls to take the
unit out of setpoint mode (status display goes from SET to blank)
2. Using a thin tool (e.g., a paper clip), press the FUNCTION switch once, then rotate either the
CURRENT or VOLTAGE control until the display reads ADDR; the active GPIB address is
visible in the DC AMPERES display. To change the address, proceed to step 3.
3. Tap the DC OUTPUT switch. The GPIB address visible in the DC AMPERES display begins
blinking.