GE 8085-FC-10 20 + 24 pin cables for 8619 (1m)
Power and communicationCarriers distribute “system” power to IO
Modules and provide the communications
route between Controllers and IO Modules.
(Controller power is supplied by direct
connections to the Controllers themselves).
IO Module Carriers provide connectors
through which field power can be supplied
(see “Bussed Field Power”). Note: field
power to Intrinsically Safe IO is managed
differently, see the relevant 2/1 data sheets.
Multi-pin connectors at the end of each
carrier allow further Carriers to be added–
and the “system” power supply and
“Railbus” connections to be made.
Earthing screens and shields
All I/O Module Carriers have their own
independent earthing/grounding strip
to terminate the screens/shields of field
wiring cables.
SafetyNet Controller Carrier
The SafetyNet Controller Carrier (8751-CA NS) is the dedicated Carrier for the
SafetyNet System. It can support simplex or
redundant SafetyNet Controllers and the
Power Supply Monitor (8410-NS-PS).
Serial communications
Two D-type connectors are provided on the
SafetyNet Controller Carrier for connecting
to serial devices. These link to Serial Port “1”
of Controller A and Controller B.
A second pair of D-type connectors is found
on the Controllers themselves, to provide
connections to Serial Port “2” where
redundant serial communication is required.
Further details of the serial port connections
are given in the data sheet for the SafetyNet
Controllers and Carriers.
Controller Carriers
Two Controller Carriers are available - the
standard Controller Carrier and the ELFD
Controller Carrier.
To comply with the earth leakage fault
detection (ELFD) requirements of Fire & Gas
application standards, the ELFD Controller
Carrier (8751-CA-NS) can be used. A single
channel of an 8811-IO-DC module must be
allocated to earth leakage detection to
implement this function.
SafetyNet applications that do not require
ELFD can use the standard Controller
Carrier (8750-CA-NS)

Change State buttons
Two change state buttons are mounted on
the SafetyNet Controller Carrier – one for
each Controller. The button is used to switch
a master to being the standby in a
redundant pair, to switch a standby offline
and to instruct an offline standby Controller
to synchronise itself with the Controller and
to enter standby.
Terminations for power fail
inputs
The 8913-PS-AC and 8914-PS-AC power
supplies each have an output that indicates
the health of the supply. These outputs can
be connected to the termination block on the
SafetyNet Controller Carrier and are used
by the Power Supply Monitor Module to
detect failures in any of up to 7 of these
external power supplies.
Module Carrier
SafetyNet Systems use the 8-module Carrier
with 64-slot addressing (8709-CA-08) for
SafetyNet and standard modules.
Up to 8 of these may be used together to
provide slots for up to 64 IO Modules.
The 4-module Carrier (8710-CA-04) can be
used where the application requires four IO
Modules or less. This will modify the
addressing system and users should should
contact MTL when considering this option.
Carrier Extenders and Cables
To allow for flexibility in cabinet layout,
Carrier Extenders are provided which –
together with the Extender Cables – are used
to connect Carriers mounted on different
sections of the cabinet backplane or DIN
rail. Carrier Extenders are used in left- and
right-hand pairs