Impulse SCMXIF - Manual

SCM7B
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Isolated Process Control Signal Conditioning Products
SCM7B
SCM7BXEV
Description
The SCM7BXEV (Figure 1 and 2) is a single channel backpanel that can accept
any of the SCM7B analog modules. It is meant to be used primarily for module
evaluation. Unlike multiple channel backpanels, the single high-level system
output (or input) signal is routed to all channel pins on the system interface
DB25 connector. The backpanel contains four standoffs to allow mounting, using
a #6 or smaller screw.
System Side - Power
Using the “V+” supply input, the power supply voltage can be as little as +14VDC.
If +15VDC is available, it is recommended that the supply be connected between
the “V+A” or “V+B” connections and “COM”; this will protect the module against
accidental supply reversal. Using both these connections with two power
supplies enables redundant operation. It is also recommended that a diode
transient absorber be installed to reduce power supply transient events from
degrading system performance. An “accessory” location, between the supply
and common lines, is provided for this purpose. The backpanel is fused at
1/4 Amp for module protection.
System Side - Signal
The SCM7BXEV uses either the SCM7BXCA01 (DB25 to 26-pin adapter
cable) and SCMXCA004-XX (26-pin to 26-pin interface cable), or the
SCM7BXCA02 (DB25 to DB25 interface cable), depending on system
requirements.
Figure 1: SCM7BXEV Dimensions
Specifications
Operating Temperature –40°C to +85°C
ATEX Group II, Category 3 –20°C to +40°C
Relative Humidity 90%
Interface Connector:
Field high density screw clamp, 10-24 AWG
System DB25 (male) with 4-40 screwlocks and
high density screw clamp, 10-24 AWG
Field Side - Signal
On the field side, a temperature sensor is mounted underneath the field side
terminal block to provide cold junction compensation for thermocouple modules,
and a current-to-voltage conversion resistor (P/N SCM7BXR1) socketing
location is provided (supplied with SCM7B33 modules). Field connections are
terminated with three screw terminals
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Accessories for SCM7B Analog Modules