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INSTRUMENTS
5.5.3 Advanced Parallel Operation
In Advanced Parallel operation the master unit displays the total current of all units connected in
Parallel. The slave units display ”
ON SE
”. The master and slave units operate in a Daisy-Chain
connection configuration. For further details about Daisy-chain connection refer to section 5.6.
In the Advanced Parallel mode, the total current is programmed and reported by the master unit.
The Current display accuracy is 2%+/- 1 count. In cases where higher accuracy is required, it is
recommended to use Basic Parallel operation mode.
5.5.3.1 Master Unit Set Up
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.
1. Press MENU button.
2. Rotate Voltage encoder until ”
r
” appears on Voltage display, then press Voltage encoder.
3. Rotate Current encoder and select required ‘n’ value (from 2-6) for example, ”
H3
”. The display
blinks once and returns to previous level. Refer to Table 5-2.1.
4. 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.
5. Recycle AC power.
6. If there is more than one Slave unit connected to the Master, then set the PS_OK signal delay
of the Master to 200msec. Refer to section 5.7.4 Power Supply OK Signal.
5.5.3.2 Slave Unit Set Up
When Advanced Slave mode is selected the power supply enters Current programming mode
via external Voltage. Voltage and Current programming setting values are set to 105% of range.
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. This helps reduce imbalance which may occur by cabling and
connections voltage drop.
When a unit is programmed to Advanced Slave mode it enters Remote mode with Local Lockout.
In this mode, Front panel controls are disabled to prevent accidental setting change except Menu
parallel setting and factory reset. Communication commands are disabled. Power supply responds
only upon query.
1. Press MENU button.
2. Rotate Voltage encoder until ”
r
” appears on Voltage display, then press Voltage encoder.
3. Rotate Current encoder until ”
SAD
” appears.
4. Press Current encoder to select ”
SAD
”. Display blinks once and returns to previous level.
5. Recycle AC power.
6. For wiring instructions, refer to Fig.5-4: Parallel connection with local sensing or Fig.5-5:
Parallel connection with remote sensing and Section 5.6: Daisy-Chain connection.
NOTE:
To release units from Advanced mode select ” H1 ”.
SO
SO