Module #9 Service Operations, Enter Access Code

MODULE #9 - SERVICE OPERATIONS

The indicator has been fully calibrated at the factory. If the unit appears to be indicating incorrectly or inaccurately, refer to the troubleshooting section before attempting this procedure.

When re-calibration is required (generally every 2 years), this procedure should only be performed by qualified technicians using appropriate equipment. Resistance source accuracies of 0.01% or better are required.

The procedure consists of applying accurate signal levels to the indicator in a series of two steps. Allow a 30 minute warm-up period before starting this procedure.

Note: Once the access code has been entered, there is no exiting the program module without completing the calibration procedure.

ENTER ACCESS CODE

“Code 48” must be keyed-in prior to the calibration sequence to guard against inadvertent entries. Access code numbers other than those listed in this section should not be entered at this step. If any are entered, undefined or unpredictable operation could result.

“CodE” < > “0” to “99”

If the code number for the previous step was not recognized, the indicator returns to “Pro 0”, with no action taken. Otherwise, the calibration procedure is started.

ENTER ZERO REFERENCE

Apply 0 ohms to input by shorting Terminals 6 and 7 as shown in the drawing to the right. Allow to stabilize for 20 seconds before pressing “P”.

“StEP 1” (Press “P”)

APPLY PRECISION RESISTANCE

Connect a precision (0.01%) 5.11 K resistor across

Terminals 6 and 7.

Allow to stabilize for 20 seconds before pressing “P”. “StEP 2” (Press “P”)

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Indicator calibration is complete. It is recommended that calibration be checked by comparing the displayed temperature with a precision thermometer.

SERIAL HARDWARE (loop-back) DIAGNOSTICS

The internal serial communications hardware in the IMY can be tested to verify proper operation. The procedure consists of connecting the Serial Input (SI), Serial Output (SO), and

20 mA Source into a simple loop, and then entering an access code.

Connect the IMY as shown at right. Enter “Pro 9”, key-in “Code 39”, and then press “P”. If the serial communication hardware is OK, “PASS” will be displayed.

Conversely, if there is an internal problem, “FAIL” will be displayed. After the diagnostic test is complete, press “P” to return to “Pro 0”.

“CodE” < > “39”

RESTORING ALL PROGRAMMING PARAMETERS BACK TO FACTORY CONFIGURATION

All of the programming in Modules #1 through #8 can be restored back to the factory configuration by entering a specific access code (refer to the “Factory Configuration” section for the data that will be entered). The procedure consists of entering “Pro 9”, keying-in “Code 66”, then pressing “P”. The IMY responds by displaying “INItAL” for several seconds, and then returns to “Pro 0”.

Note: When this procedure is performed, all of the scaling, presets, etc. that were programmed into the IMY will be overwritten.

“CodE” < > “66”