Omega Vehicle Security 1400 manual Enter J3,3,0000.0X J6,3,0000.0X J11,3,0000.0X J14,3,0000.0X

4.Type U2X to verify calibration mode. U128 should appear, indicating the unit is in calibration mode.

5.Enter commands similar to those in the first two columns in the following table. This example is for a T/C card in slot #1, and a Type 3 (“T” type) thermocouple. The table on the preceding page provides additional channel numbers to use as they apply to your system.

Enter: J3,3,0000.0X

J6,3,0000.0X

J11,3,0000.0X

J14,3,0000.0X

After each calibration enter U2X,

then observe U128 indicating no errors.

Note: The number after the J is the channel number, the next number is the thermocouple “type,” and the number preceding the X is the temperature in °C. Thus, J3,3,0000.0X means “Calibrate cold junction offset for channel 3, type 3 (T-type) thermocouple at 0°C.

Response codes and meanings applicable to calibration are as follows:

Response to U2X	Indication for Calibration Mode
U128	No error
U129	Read Failure (EEPROM Error)
U130	Write Failure (EEPROM Error)
U132	Chksum Err (EEPROM Error)
U136	Cal Err (offset, gain, or temperature sensor out of range)
U144	Invalid password
U160	Invalid command

7.Verify calibrated temperature using one of the following three options. Note related figure on following page.

a)Cold Cell Method. Connect Cold Cell simulator to the T/C card’s 4 CJC reference channels and to the DC voltage calibrator, as indicated in the following illustration, figure (a). Adjust the calibrator voltage to match that of the desired test temperature using Voltage-to-Temperature Reference Tables. Verify the channel readings match the test temperature for each of the four CJC reference channels. Repeat verification for all T/C cards.

Note: The Cold Cell Simulator in figure (a) shows a special connection box attached to it. This connection box, which can be easily made, is not part of the cold cell device.

b)Hot Cell Method. Connect Hot Cell simulator to T/C card’s first CJC reference channel. Adjust Hot Cell to obtain desired test temperature and ensure temperature is stabilized. Observe channel reading to match test temperature. Repeat test for remaining three CJC reference channels. Repeat verification for all T/C cards.

c)T/C Calibrator Method (see note). Connect a thermocouple calibrator/simulator to the first ChartScan, or NetScan, CJC channel in accordance with the calibrator/simulator manufacturer’s instructions. Certain simulators will require the use of specific type T/C extension wire to create a cold junction at ChartScan’s, or NetScan’s, input; while other simulators require copper wire and reduce the output voltage as a function of ambient temperature to create the effect of a cold junction at the main unit. Adjust the output setting to the desired temperature and verify the channel reading is within the range of ChartScan’s, or NetScan’s, tolerance band for the T/C type and temperature. Repeat test for remaining three CJC reference channels. Repeat this test for all thermocouple type signal conditioning cards.

The T/C Calibrator/Simulator Method is not recommended because, unlike voltage calibrators, T/C Calibrator/Simulators have no provisions for remote sensing (and are therefore more readily subject to the transient effects of sampled data acquisition systems, such as ChartScan and NetScan). These transient effects can cause erroneous readings, even when both units are calibrated within specifications.

ChartScan User’s Manual Calibration 6-19