KEPCO BOP-GL 1KW Operator Manual Firmware Ver.3.05 and higher - Manual (Page 80)

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BOP-1K-GL 022814
3.4.2.1 USING LESSER OF DIGITAL VS. ANALOG (EXTERNAL) LIMITS
The BOP provides the ability to automatically choose the lesser absolute value between the
external limits (applied to Analog I/O port pins 5, 6, 13 and 14) and the limits established by a
digital command. This feature is accessible through digital control and can be restored upon
power-up using a saved location.
For example, with a BOP 50-20GL, the maximum limit value in current mode can be set to 20V
using the digital interface, but the limits can be controlled by the analog limit signals applied to
pins 6 and 14 of the analog I/O port. However, if the signals at pins 6 or 14 exceed 4V (10V = full
scale or 50V, 4V is 2/5 of full scale = 20V), the digital limit will take effect and prevent the limit
from exceeding 20V. To implement this send the following commands:
VOLT:PROT 10 Sets the positive and negative protection to 10 volts.
VOLT:PROT:MODE LESS Allows protect limit to be automatically selected from either 1)
the external analog voltage applied to the Analog I/O port or 2)
10V set by VOLT:PROT 10. Whichever limit has a lower abso-
lute value (closest to zero) has effect.
FUNC:MODE CURR Sets the output to current mode.
CURR:MODE EXT Sets main channel (current channel) to use an external level
applied to the Analog I/O port.
To restore the above settings for power up, send *SAV2. This saves the settings to memory
location 2 (locations 1 through 15 can be used to establish initial power-up conditions). Set
power-up switch S3 to 00010 to (S3-2 to 1) when performing a normal power-up (PAR. 3.3.2.2)
to restore the saved settings from location 2 upon power up: Current mode, External limits
enabled, limit to be the lesser of 10V (digital) or external limit signals applied to Analog I/O port.
3.4.3 MONITORING OUTPUT CURRENT USING AN ANALOG SIGNAL
The BOP provides output analog signals which are always available, 0 to ±10V, proportional to
the output current and voltage. The current monitor signal is available at pin 3, referenced to pin
4, of the Analog I/O port. The voltage monitor signal is available at pin 15, referenced to pin 4, of
the Analog I/O port.
3.5 DIGITAL CONTROL
3.5.1 PASSWORD PROTECTION
The Password is only effective when using digital control. The commands that can be password
protected are SYST:SEC:IMM and all CALibration commands. When the unit is shipped, the
password is set to DEFAULT. Refer to PAR B.139 to set a new password.
Before performing calibration or sending SYS:SEC:IMM, first send SYST:PASS:CEN (see PAR
B.137). When calibration is complete or when SYST:SEC:IMM has been executed, it is recom-
mended that the password state be disabled using SYST:PASS:CDIS (see PAR B.138).
3.5.2 SETTING OPERATING MODE (VOLTAGE OR CURRENT)
The BOP uses two separate channels, one to set output voltage or current and one to set the
corresponding protection limit. When using digital control, the main channel is determined by
the FUNC:MODE command which selects either Voltage mode or Current mode, or allows the
status of Analog I/O port pin 2 to determine the mode (see PAR. 3.3.10 for details). The limit