Micromod RetroPAK: MOD 30 Installation Manual User Manual
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MOD 30ML Replacement for MOD 30 Instruments
REPLACEMENT CONSIDERATIONS
2.4
INDICATOR
The MOD 30 indicator requires a single interconnecting cable to carry power and I/O
signals between the instrument and the termination panel. The replacement instrument
uses this same cable. The full complement of 5 I/O points can be accommodated by the
replacement instrument. The I/O signals are as follows:
•
3 Analog Inputs
•
3 Digital Outputs (Model B only)
The replacement instrument accepts analog inputs No. 1 and No. 2 via built-in input
circuits 1 and 2 as indicated in Table 2-1. An analog input module (Catalog No. 2001A)
must be installed in location S4 to provide the third analog input. Digital output modules
(2007A) must be installed in locations S3, S4 and S5 to provide digital outputs No. 1,
No. 2, and No. 3.
Since the MOD 30 Indicator does not communicate over the ICN, the replacement
instrument must be configured via the RS-232 port in the front panel (see Section 2.2.1).
2.5
MATH UNIT
The MOD 30 math unit requires two interconnecting cables to carry power, ICN
communication, and I/O signals between the instrument and the termination panel. The
replacement instrument uses both of these cables. The full I/O complement for the math
unit is as follows:
•
6 Analog Inputs
•
2 Analog Outputs
•
7 Digital Inputs
•
7 Digital Outputs
The 22 I/O points available in a math unit are not fully covered by the replacement
instrument which can accommodate only 15 I/O points. The combination of built-in and
modular I/O in the replacement instrument does accommodate many math unit I/O
combinations. For example, a possible arrangement using all 15 available points can
provide an I/O combination as follows:
•
4 Analog Inputs
•
2 Analog Outputs
•
5 Digital Inputs
•
4 Digital Outputs
In this example, 2 analog inputs and 2 analog outputs are accommodated by the built-in
I/O circuits. The remaining 11 points are handled by the modular I/O.
Use the Math Unit I/O planning form to record the required modules and their locations for
a specific application. An example of the form filled in to document the above example is
shown in Figure 2-2. Note that the built-in circuit is specified for the ICN so that all module
locations are available for I/O signals (see Section 2.2.1). See Appendix A for a blank
copy of the planning form.
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