Allen-Bradley 1794-IE8H, Руководство пользователя, Страница: 79 / 146

Publication 1794-UM063A-EN-P - March 2006
Calibrate Your Module 5-11
1794-OE8H Calibration
Features
The following features are unique to the 1794-OE8H module:
•
There are six values per channel that the I/O module uses to calculate
the corresponding calibration values (offset and gain).
– Min Scale DAC at 1500
dec
about 1 mA
– Max Scale DAC at 6700
dec
about 20 mA
– Current-read-back Min Scale at 1500
dec
about 1 mA
– Current-read-back Max Scale at 6700
dec
about 20 mA
– Voltage-read-back Min. Scale at 1500
dec
– Voltage-read-back Max Scale at 6700
dec
•
The module internally calculated calibration values are:
– Offset DAC
– Gain DAC
– Offset I-read-back
– Gain I-read-back
– Offset U-read-back
– Gain U-read-back
•
All calibration values are stored in the module nonvolatile EEPROM.
•
Only one channel can be calibrated at a time according to one
calibration value (max scale or min scale values).
•
The actual date must be transmitted after calibration to the I/O module
and stored in the module nonvolatile EEPROM. The data can be read
out over the EDT channel.
•
The whole calibration can be set to default values by sending a reset
command. The default date is Jan,01,2000.
•
A specified calibration value can be set to default by sending a reset
command for that channel.
•
There is a special command to store the whole calibration data from
RAM to EEPROM within the I/O module.
•
If one value, except the calibration date, isn’t calibrated yet, or if you set
one value to default, the I/O module displays a calibration error within
the Real Time Data diagnostic field.