TDK Lambda | Z+Low Voltage User Manual

5.5 Parallel Operation 5.5.1 Introduction

Up to six units of the same Voltage and Current rating can be connected in parallel to provide up to six times the output current capability. One of the units operates as amaster 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. TheMaster and Slavemodes are stored in the power supply EEPROMwhen the AC power is turned off. The system will return to the Master/Slave mode upon re-application of AC power. There are twomethods to configuremultiple supplies for parallel operation (basic and advanced). Refer to Section 5.5.2 and to Section 5.5.3 for detailed explanation. Parallel modes are selected via Front Panel menu. Refer to table 5-2. Subsystem Level Function Level Parameter Level Description Display Function Display Description Display

Single power supply



O

Master

2

Host /Basic Slave / Advanced Slave

Parallel Operating Mode



Slave (Basic)





Slave (Advanced)



Table 5-2. Parallel subsystem menu

Display

Operating Mode

Single unit (default)

H1 H2 H3 H4 H5 H6 SL

Master unit with 1 Slave unit Master unit with 2 Slave units Master unit with 3 Slave units Master unit with 4 Slave units Master unit with 5 Slave units

Slave unit (Basic mode)

Slave unit (Advanced mode)

SLAd

Table 5-2.1: Operation Setting Mode

5.5.2 Basic Parallel Operation In this method, setting the units as Master and Slaves is made by the rear panel J1 connections and setup via Front Panel. Each unit displays its own output current and voltage. To program the load current, the Master unit should be programmed to the total load current divided by the number of units in the system. The master and slave units operate in a Daisy-Chain connection configuration. For further details about Daisy-chain connection refer to section 5.6. Refer to the following procedure to configure multiple supplies for basic parallel operation. 5.5.2.1 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. Front Panel Main Menu Parallel mode is ”  ” as default. 1. Press MENU button. 2. Rotate Voltage encoder until ”  ” appears on Voltage display, then press Voltage encoder. 3. Rotate Current encoder until ”  ” appears. 4. Press Current encoder to select ”  ”, the display blinks once and returns to previous menu level. 5. 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. 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.

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