Operation; Installation Requirements - Siemens ET 200M Manual

17.3

Operation

Power is supplied via the two removable power connectors which are retained by
screws and marked L+A, MA, and L+B, MB. Each has a LED to indicate the
presence of voltage over 15 VDC. The LEDs are marked A POWER and B
POWER. There is also a connector for a Power Monitor board used to indicate the
presence of both A and B power. See Section 19, Power Monitor Board (6ES7650-
1BA02-0XX0).
Incoming power from A and B is diode OR'd to provide the MTA and the module
power from either input source. The output is sent to the I/O modules via the
module fuses and to the channels via the channel fuses. Module 1 Fuse supplies
the I/O Module plugged into the Module 1 connector and Module 2 Fuse 2
supplies power to the I/O Module plugged into the Module 2 connector.
Field Terminals, Normally Closed (NCx), Common (COMx), and Normally Open
(NOx) connect to the field devices. NCx and COMx are used to provide a normally
closed connection when the relay is not energized. NOx and COMx are used to
provide a normally open connection when the relay is not energized. The field
termination connector is removable for ease of wiring maintenance and is retained
by friction.
The relay coil x connects to the I/O modules input via the channel fuse to the
Module 1 and Module 2 connectors. Redundant operation uses two modules with
one each connected to the Module 1 and Module 2 connectors. Redundant
operation is achieved by connecting the diode output from each channel on
different modules together. Non-redundant systems have one module connected to
either the Module 1 or Module 2 connectors.
17.4

Installation Requirements

See Section 2, Installation, before performing any installation and observe all
warnings
A common interconnecting cable (6ES7922-3BD00-0AS0 and 6ES7922-3BJ00-
0AS0), supporting 10 DO channels, interconnects the discrete output termination
assembly to the 10-channel, 24 VDC Failsafe discrete output module (6ES7 326-
2BF10-0AB0, E-Stand 3 or higher).
Note
To disconnect the interconnecting cable shield from ground at the MTA only, cut
and remove the shield disconnect jumper, item 5, for the associated cable. See
Figure 17–.
Marshalled Termination Assemblies for ET200M Remote I/O Modules
A5E00482820-12
Failsafe 10-Channel, 24-150 VDC/120-230 VAC Relay Output MTA
221