CAT EMCP 4 - 6.3 DATA INVALID - OUTSIDE OF DATA RANGES

Application and Installation Guide EMCP 4 SCADA Data Links
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131 (0X83) – EXCEPTION RESPONSE TO READ REGISTERS QUERY
The exception response contains a 1-byte exception code.
Code Reason
01 Starting or ending (starting + count) register address invalid
02 Register Count was less than 1 or greater than 125
03 Read error possibly due to some register(s) in the span not being Read registers
134 (0X86) – EXCEPTION RESPONSE TO WRITE SINGLE REGISTER QUERY
The exception response contains a 1-byte exception code.
Code Reason
02 Register address invalid
03 Register value out of range perhaps because longer than 2 bytes
04 Write error possibly due to not being a Write register
144 (0X90) – EXCEPTION RESPONSE TO WRITE MULTIPLE REGISTERS QUERY
The exception response contains a 1-byte exception code.
Code Reason
02 Starting or ending (starting + count) register address invalid
03
Register Count was less than 1 or greater than 123, or byte count was not
(Register Count x 2)
04 Write error possibly due to some register(s) in the span not being Write registers
OTHER 128 AND ABOVE (0X80 AND ABOVE) – EXCEPTION RESPONSE TO UNSUPPORTED QUERIES
The EMCP 4 does not support any function codes not listed above in the Supported Function Codes
Chapter. Such queries will return an exception response with this 1-byte exception code.
Code Reason
01 Unsupported function code
6.3 DATA INVALID – OUTSIDE OF DATA RANGES
If the EMCP 4 returns data, the client must interpret that data correctly. For each piece of data, there is a
certain range of data that is defined as valid data. See section 4.3 for explanations of data interpretation
and data ranges. If the data is not within the defined valid data range, here are several possible reasons:
 The data is expected over either the Primary or Accessory Data Link, and is not being received
 The sensing inputs providing the data is detecting a fault (e.g., open circuit, short circuit)
 The EMCP 4 has determined a logical flaw with the data being detected (e.g., generator circuit
breaker aux A and aux B either both closed or both open)
 The data is expected over an input, but no input is configured to provide it
 The data is expected over either the Primary or Accessory Data Link, and is being received as a
fault due to problems with the module or the connection