Omega Engineering OM5-C, Руководство пользователя

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4
OM5-IMV/IV
Analog Voltage Input Modules, Narrow Bandwidth
FEATURES
●
ACCEPTS MILLIVOLT AND VOLTAGE LEVEL SIGNALS
●
HIGH LEVEL VOLTAGE OUTPUTS
●
1500Vrms TRANSFORMER ISOLATION
●
ANSI/IEEE C37.90.1-1989 TRANSIENT PROTECTION
●
INPUT PROTECTED TO 240VAC CONTINUOUS
●
160dB CMR
●
95dB NMR AT 60Hz, 90dB at 50Hz
● ±
0.05% ACCURACY
● ±
0.02% LINEARITY
● ±
1
µ
V/
°
C DRIFT
●
CSA CERTIFIED, FM APPROVED, CE COMPLIANT
●
MIX AND MATCH OM5 TYPES ON BACKPANELS
FIGURE 1. OM5-IMV/IV Block Diagram.
DESCRIPTION
Each OM5-IMV and OM5-IV voltage input module provides a single
channel of analog input which is filtered, isolated, amplified, and converted
to a high level analog voltage output (Figure 1). This voltage output is
logic-switch controlled, allowing these modules to share a common analog
bus without the requirement of external multiplexers.
The OM5 modules are designed with a completely isolated computer side
circuit which can be floated to
±
50V from Power Common, pin 16. This
complete isolation means that no connection is required between I/O
Common and Power Common for proper operation of the output switch. If
desired, the output switch can be turned on continuously by simply
connecting pin 22, the Read-Enable pin to I/O Common, pin 19.
Signal filtering is accomplished with a six-pole filter which provides 95dB
of normal-mode-rejection at 60Hz and 90dB at 50Hz. Two poles of this filter
are on the field side of the isolation barrier, and the other four are on the
computer side.
After the initial field-side filtering, the input signal is chopped by a
proprietary chopper circuit. Isolation is provided by transformer coupling,
again using a proprietary technique to suppress transmission of common
mode spikes or surges. The module is powered from +5VDC,
±
5%.
A special input circuit on the OM5-IMV and OM5-IV modules provides
protection against accidental connection of power-line voltages up to
240VAC.
LPF
+In
–In
–EXC
Backpanel
Term Block
1
2
NC
6
5
3
NC
Surge
Suppression
and
Protection
Isolated
Field-Side
Power
4
3
2
1
+EXC
–V
+V
V
IN
4
NC
–V
LPF
+V
Power
Oscillator
Isolated
Computer-Side
Power
V
OUT
20
22
I/O Common
RD EN\
+5V
17
16
Power Common
NC
19
Isochopper™
Amplifier
Pat Pending