Rockwell Automation 1395 Digital Reference Adapter Board - Manual (Page 36)

Chapter 5
Programming Parameters
5-11
analog to digital converter. There, it is converted to a +2048 digital
value prior to being digitally scaled, digitally offset and used by the
drive. Before the digital value is displayed or transferred to the drive,
the Scale Factor is applied, thus allowing an effective digital range of
+32767(16 times 2048). The absolute digital value is clamped at 32767.
Parameter 553 – [A > ADC Offset 2]
Parameter 503 – [B > ADC Offset 2]
Use : Digital Offset for Analog Input 2
Programming Terminal units: Volts
Minimum Value: – 20 VDC
Maximum Value: + 20 VDC
Default Value: 0 VDC
Description: This parameter determines the offset applied to the output
value of the analog to digital converter of Analog Input 2, before the
digital scale factor is applied. This allows the user to shift the range of
the analog input.
Parameter 554 – [A > Analog PR GN 1]
Parameter 504 – [B > Analog PR GN 1]
Use : Analog Programmable Gain for Analog Input 1
Programming Terminal units: None
Minimum Value: 0
Maximum Value: 4
Default Value: 0
Description: This parameter digitally determines the analog gain for
Analog Input 1. The only allowable values for this parameter are per the
following table:
Table 5.B
VALUE
0
1
2
3
4 GAIN
1
2
4
8
16
This analog gain is applied to the Analog Input 1 after the analog offset
is applied so that the input signal can have any appreciable offset
removed prior to being amplified. The amplification is important in
order to provide as much signal resolution to the input of the analog to
digital converter. In addition, if necessary, this gain can be modified
actively during Drive operation to provide programmable trim gain
should the application require it.