Ea Elektro Automatik EA Elektro-Automatik 06230319, 1 Output Variable DC Power Supply, , Bench 06230319 Hoja De Datos

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EA Elektro-Automatik GmbH

Helmholtzstr. 31-33 • 41747 Viersen

Germany

Fon: +49 2162 / 3785-0

Fax: +49 2162 / 16230

Multiple devices of same kind and model can be connected in parallel in order to create a system with higher total 

current and hence higher power. For master-slave operation, the units are usually connected with their DC outputs, 

their Share bus and their digital master-slave bus. 
The master-slave bus is a digital bus which makes the system work as one big unit regarding adjusted values, 

actual values and status.
The Share bus is intended to balance the units dynamically in their output voltage, especially if the master unit 

runs a function like sine wave etc. In order for this bus to work correctly, at least the DC minus poles of all units 

have to be connected, because DC minus is the reference for the Share bus.
Compared to normal operation of a single device, master-slave operation has some restrictions:
•

The MS system reacts differently to alarm situations (see below in 3.10.1.5)

•

Resistance setting and control (CR) is not available. In case, master-slave is not activated in the menu of the 

devices, switching to and use of R mode is not blocked, but R mode will not work correctly in a parallel connection

•

Using the Share bus makes the system reacts as dynamically as possible, but it is still not as dynamic as  single 

unit operation

3.10.1.1  Wiring the DC outputs
The DC output of every unit in the parallel operation is simply connected to the next unit using cables with cross 

section according to the maximum current and with short as possible length.
3.10.1.2  Wiring the Share bus
The Share bus is wired from unit to unit with an ideally twisted pair of cables with non-critical cross section. We 

recommend to use 0.5 mm² to 1.0 mm². 

3.10.1.3  Wiring and set-up of the master-slave bus
The master-slave connectors are built-in and can be connected via network cables (≥CAT3, patch cable). After 

this, MS can be configured manually (recommended) or by remote control. The following applies:
•

Type of connection: RS485 with 115200 Bd

•

A maximum 10 units can be connected via the bus: 1 master and up to 9 slaves.

•

Only devices of same kind, i.e. power supply to power supply, and of the same model, such as PSI 9080-60 2U 

to PSI 9080-60 2U.

•

Units at the end of the bus must be terminated (see below)

Later operation of the MS system implies: 
•

The master unit displays, or makes available to be read by the remote controller, the sum of the actual values 

of all the units

•

The ranges for setting the values, adjustment limits, protections (OVP etc.) and user events (UVD etc.) of the 

master are adapted to the total number of units. Thus, if e.g. 5 units,  each with a power of 1.5 kW, are connected 

together to a 7.5 kW system, then the master can be set in the range 0...7.5 kW.