How to configure MV-90 to resolve communications problems for devices that consistently have communications or time-out errors.

Goals and Symptoms

This article introduces 3 useful MV-90 configuration parameters which could help to solve communication problems for devices that consistently have communication errors or time-out errors.

Causes and Fixes

Steps to configure MV-90:
1) Create a .cfg file with the following configuration parameters by using notepad.
i) Record Buffering setting
RECBUF=n
The value of n is an integer number between 1 and 15, which represents the number of records that should be read with each communication with the meter. The TIM module will use this parameter at the beginning of the interrogation and will dynamically reduce the number of records read with each command if communication errors are encountered. For interrogations performed over a slow communication link, we recommend that n be set to 15. For devices that consistently have communications errors, a setting of 1 is recommended. Default Value = 15.

ii) Severe Timeout setting
TO=n
The value of n represents the amount of time the TIM waits for a response from the meter in hundredths of a second. This setting should only be used if the TIM is failing interrogations with an I/O Timeout Error (return code 22). If this happens, attempt to use a bigger number that will allow the meter interrogations to complete consistently. Default Value = 300.

iii) Intra-byte Timeout
ITO=n
This parameter sets the inter-character timeout that is used by the TIM. The value n represents the amount of time in hundredths of a second the TIM will wait for each byte within a response. The value required depends greatly on the meters processing speed, the requirements being placed on the meter by the programming, Default Value = 100.

2) Place the .cfg file in the ..\MV90xi\master folder.

3) Specify the TIM configuration file name (e.g. 8600p.CFG) in the 'TIM Config File' field under the More tab of the concerned recorder: