Micromod MOD: 30ML Functions Data Base Reference - Manual (Page 137)

MOD 30ML Functions
CONFIGURATION EXAMPLES
The CJC compound resides in the utilities section of the Application Builder software. It is
accessed via the compound icon in the application builder tool bar, and can be loaded into a
strategy at either the instrument level or the loop level. When loaded, the CJC compound
appears in the workspace as a state compound. Input and output connections to the CJC
function can be made either at the instrument level or at the loop level The cold junction
compensation signal within the compound can be connected to a series of thermocouple
input module blocks so that only one CJC compound is required to compensate all
thermocouple input modules in an instrument.
The blocks which make up the CJC compound are shown in Figure 3-6. Each block has
been preconfigured and all required connections between the blocks have been made. Each
block can be queried to view its edit display. CJC parameters such as thermocouple type,
temperature scale, I/O module location etc., can be configured on the edit displays.
3.3.14 Configuration Procedure
The starting point of this procedure is the level (instrument level or loop level) where the CJC
compound appears in your strategy. The CJC compound can be added to an existing
strategy which was saved previously or it can be used in a new strategy which has been
initiated as described in Section 3.3.
Configuring CJC Parameters
The parameter values for the CJC function are determined by configuration of the attributes
of the blocks within the CJC compound. These attributes appear on the edit displays
associated with each block, and each attribute has an assigned default value. In general the
default values are satisfactory for most applications. Those attributes relating to the
instrument hardware configuration and specific process values (i. e., module location,
thermocouple type, temperature scale etc.) may require adjustment. The default values can
be edited as follows:
1. Double click on the CJC compound to open it and see the blocks which make up the
compound.
2. Choose the option to be used in your strategy:
• Option 1: Temperature at the instrument terminals is not available for display.
• Option 2: Temperature at the instrument terminals is available for display.
3. For the option chosen, edit the attributes of each block as follows:
a. Double click on a block to access its edit display.
b. Review the default values for each attribute and change values if required.
Attributes most likely to require changes are:
• Module Location ( TIM1 or TIM2 Block)
Enter the slot number for the TIM (Thermocouple Input Module).
• Module Location (RIM1 or RIM2 Block)
Enter the slot number for the RIM (RTD Input Module)
• Thermocouple Type (TIM1 or TIM2 block)
Scroll entry to obtain required thermocouple type.
• Temperature Scale (TI1 or TI2 block)
Scroll entry to obtain required temperature scale.
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