KEPCO MBT Series - Manual (Page 39)

MBTSVC111609
3-1
SECTION 3 - OPERATION
3.1 GENERAL
The MBT Power Supply can be operated in either Local or Remote modes. Upon turn on, the
Power Supply is in Local mode and restores the settings in place at previous turn off. The fac-
tory default settings for Voltage and Current are 0, Voltage Mode selected and, for MR and
MGR units, Non-reversed Polarity. MG and MGR (“G” option) units require initialization of the
SBC (single board computer), resulting in an additional initial delay.
Operation of the power supply requires an understanding of how the power supply works. The
MBT power supply is a linear power supply with an automatic crossover between Voltage mode
and Current mode. To avoid confusion, a distinction must be made between actual mode (the
actual mode the power supply operates in) and the commanded mode (the mode the power sup-
ply is commanded to enter either by keypad operation (either locally or remotely) or remotely by
a command issued by computer via a controller.
3.1.1 ACTUAL MODE
If the output is enabled, the unit will be in actual Voltage mode as long as the load is greater
than, or equal to, the value of programmed voltage divided by programmed current.
If the output is enabled, the unit will be in actual Current mode as long as the load is less than
the value of programmed voltage divided by programmed current.
If the output is disabled, M and MG Models will always be in actual Voltage mode; for MR and
MGR models the actual mode will be the same as the commanded mode.
The STATUS indicators (VOLTAGE MODE and CURRENT MODE) always reflect actual mode.
When the unit operates in actual Voltage mode, the power supply will maintain the output volt-
age constant at the value programmed for Output Voltage; current will vary in accordance with
the value of the load within the limits established by programmed Current Limit. When the unit
operates in actual Current mode, the power supply will maintain the output current constant at
the value programmed for Output Current; the output voltage will vary in accordance with the
value of the load within the limit established by programmed Voltage Limit.
Note that V
PROG
and I
PROG
are either output or limit parameters, depending on the actual mode:
When the unit is in actual Voltage mode, V
PROG
refers to Output Voltage and I
PROG
refers to
Current Limit; when the unit is in actual Current mode, V
PROG
refers to Voltage Limit and
IPROG refers to Output Current.
VOLTAGE MODE (V
OUT
V
PROG
) when R
L
V
PROG
I
PROG
--------------------- ≥ =
CURRENT MODE (I
OUT
I
PROG
) when R
L
V
PROG
I
PROG
--------------------- < =
SECTION 1 -
SECTION 2 -