Rev 20.11.2019
V1.07 - Page 6
Subject to modifications!
romutec Steuer.-und Regelsysteme GmbH Jochsberger Straße 39 D-91592 Buch am Wald
www.romutec.de
Subject to technical changes
4 Configuration
4.1 Hardware
Maximum number of expansion modules per MODBus interface
Basically, as many romod devices can be connected to a bus interface as addresses can be set. The
complete address range of 0 ... 254 is available. However, please adhere to the
DDC’s manufacturer's
recommendations concerning the maximum number of slave devices which may be connected to the bus
interface of the master device, as well as any constraints given for the address range.
Installation and wiring
Installation and wiring of the modules which are containing the hardware IOs will be done in the cabinet on
the mounting plate.
Addressing
The address which is used for communication with the
module has to be set by means of a dip switch in the range
of 0 ... 254. Dip #1 (most left) represents the value 1, Dip #8
(most right) signifies the value 128.
The following should be considered when setting the
addresses:
There are not allowed any duplicate addresses. Each
address can be assigned only once per MODBus line.
The addresses can be selected arbitrarily in the range of
0 ... 254, setting sequential addresses is not necessary.
Note:
When setting the address 255, the device
performs a reset followed by a lamp test. Doing so, all
parameters stored in the EEPROM will be reset to
factory settings.
Important:
This also happens during
operation, without de-energizing the module in the
meantime!
Using the EOL switch (two pin dip switch), the bus can be terminated (active termination, 560R /
120R / 560R).
Meaning of the status LED (valid for all modules)
The status LED is located to the right of the dip switch used for setting the address of the module.
It signals the following states:
Green
accelerated
blinking
Start-up sequence running
Steady light operational
Orange
flashing
Communicating with the master (valid
telegram received)
Red
flashing
Faulty or unvalid telegram received
