Table of Contents - TG Drives

EXTENDED REGISTER GROUPS
OptAD, analog to digital converter.
OPTAD, ANALOG TO DIGITAL CONVERTER.
Group Group
No.
Description
OptAD 22 Optional analog to digital conversion.
GENERAL
The DMC equipped with this option has an analog input named M1. This channel
has an individual gain setting. The gain setting is controlled with the
OptAD.GainM1 member. The input is intended for a strain gauges transducer i.e. a
load cell or a torque transducer. The connector also incorporates a balanced
supply voltage of +/- 5 VDC.
Channel Measuring range Purpose
M1 ±50 mVDC Strain gauge
transducer
CONVERSION RESULOTION
Extern measurement
bridge is required.
The AD resolution is 14 bit, and the result is sign extended to utilize the 32 bit PL
register set.
CALIBRATION
The M1 channel has two resistances, 390 kΩ and 47kΩ, that can be used to
calibrate an externally provided measurement bridge. When the value in the table
is written to OptAD.Cal then the selected calibration resistance will be connected in
parallel with one of the four legs in the Measurement Bridge.
Value Channel Resulting calibration resistance.
0 none Disconnect all calibration resistances.
8 M1 390 kΩ
9 M1 47 kΩ
EXAMPLE USAGE
; On startup.
OptAD.Cal = 0 ; disconnect all calibration resistances.
..
; Start calibration
OptAD.Cal = 8 ; M1, calibration resistance = 390 kOhm
R200 = OptAD.M2 ; Conversion is done within 200 us.
..
OptAD.Cal = 0 ; disconnect all calibration resistances.
; Start measuring
R100 = OptAD.M1 ;and the result is stored in R100.
; The calibration value in R200 is application dependent and
; bridge dependent, and it can be used in several different
ways.
;
; 1. Value may indicate what type of measurement
User's Manual 5.1 Inmotion Technologies AB
Doc. No.9032 0027 01 (B), Rev. 11.07.2001
135