TEXIO PU100-7.5, Instruction Manual

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5.15. PARALLEL OPERATION
Up to four units of the same VOLTAGE and CURRENT rating can be connected in parallel to provide
up to four times the output current capability. One of the units operates as a master and the
remaining units are slaves. The slave units are analog programmed by the master unit. In remote
digital operation, only the master unit can be programmed by the computer while the slave units may
be connected to the computer for voltage, current and status readback only. Follow the following
procedure to configure multiple supplies for parallel operation.
1. Setting up the Master unit
Set the master unit output voltage to the desired voltage. Program the current limit to the desired
load current limit divided by the number of parallel units. During operation, the master unit operates
in CV mode, regulating the load voltage at the programmed output voltage. Connect the sensing
circuit to local or remote sensing as shown in Fig.5-4 or Fig.5-5.
2. Setting up the Slave units
-1.The output voltage of the slave units should be programmed higher than the output voltage of
the master unit to prevent interference with the master unit's control. The current limit of each
unit should be programmed to the desired load current limit divided by the number of parallel
units.
-2.Set the rear panel setup switch SW1 position 2 to it's up position.
-3.Connect short between J1-8 and J1-12 (refer to Table 4-4).
-4.Connect J1 terminal 10 (IPGM) of the slave unit to J1 terminal 25 (P) of the master unit.
During operation the slave units operate as a controlled current source following the master output
current. It is recommended that the power system is designed so that each unit supplies up to 95%
of its current rating because of the imbalance which may be caused by cabling and connections
voltage drop.
3. Setting Over Voltage protection
The master unit OVP should be programmed to the desired OVP level. The OVP of the slave units
should be programmed to a higher value than the master OVP. When the master unit shuts down, it
programs the slave unit to zero output voltage. If a slave unit shuts down (when its OVP is set
lower than the master output voltage), only that unit would shut down and the remaining slave units
would supply all the load current.
4. Setting Foldback protection
Foldback protection if desired, may only be used with the master unit. When the master unit shuts
down it programs the slave units to zero output voltage.
5. Connection to the load
In parallel operation, power supplies can be connected in local or remote sensing. Refer to Fig.5-4
and 5-5 for typical connections of parallel power supplies. The figures show connection of two units,
however the same connection method applies up to 4 units.