DESCRIPTION OF THE ISS 900
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Manual ISS 900 · EN02 · 2016-01
2
Typical configuration of the EC 912 with the ISS 900
ESC
Enter
Ex zone 1
Safe area
RS 422
interface
RS 422
interface
ISS 900
power supply isolator
1x RS 232 or
1x RS 422
interface
24 VDC or
115/230 VAC
8 VDC
8 VDC
Functions of the ISS 900
1.
Intrinsically safe power supply unit for using the EC 912 in Ex zone 1.
The power supply isolator supplies the EC 912 with 8 VDC in an explosion-protected way. Thus,
the EC 912 can be operated in Ex zone 1. The built-in battery is retained and will start to
operate as an emergency battery in the case of a power failure so that the corrector can keep
on running even if the ISS 900 may be without power supply for some time.
2.
Decoupling the COM 1 data interface.
On the power supply isolator module, there is a decoupling element for isolating the RS 422
data interface to the EC 912 in an explosion-protected way. The user can use the decoupled
interface outside the Ex zone, in order to connect the device to external equipment, such as a
PC, a PLC, telecontrol equipment, etc., using the MODBUS protocol. If the EC 912 is
permanently supplied, this makes it possible, for example, to transmit running measured values.
