PC3000 Complete Installation guide iss 12 - Elektro-Trading

4 Channel Analogue Input Module
Calibration of resistance inputs
9-18
This applies to module variant:
PC3000/AI/VERSION3/RT4
This module use the Function Block, Analog_In_R. The block provides the following
parameters:
Input_Type 50_Ohm (0) ; 0 to 50 Ohm (-10 to 10mV)
100_Ohm (1) ; 0 to 100 Ohm (-10 to 20mV)
250_Ohm (2) ; 0 to 250 Ohm (-10 to 50mV)
500_Ohm (3) ; 0 to 500 Ohm (-10 to 100mV)
Lin_Type Lin_mV (0) ; Linear mV ranges as above
Lin_Ohm (1) ; Linear Ohm ranges as above
Pt_100 (2) ; Platinum resistance therm.
Cal_Mode Run (0) ; Normal mode
Save (1) ; Save calibration data
mV_Hi (2) ; Calibrate mV (high point)
mV_Lo (3) ; Calibrate mV (Low point)
Res (4) ; Single point resistance cal.
Cal_Hi_Pt fixed units of mV Cal point data entry
Cal_Lo_Pt fixed units of mV Cal point data entry
Cal_Res_P fixed units of Ohm Cal point data entry
C_Cal_Hi_P fixed units of mV Stored cal data
C_Cal_Lo_P fixed units of mV Stored cal data
C_Cal_Res_P fixed units of Ohm Stored cal data
Lead_Val fixed units of mV Diagnostic used during calibration.
Voltage across lead.
All other parameters identical to the Analog_In Function Block template.
The calibration process has two stages:
(1) Millivolt calibration
(2) Resistance calibration
During millivolt calibration, the sense lead input 1 ,2 , etc. must be connected to the
L L
respective positive input 1+, 2+ etc. by a short external wire link.
Remove the links fitted to the pcb, LK101, LK201, LK301, LK401 (only 4 links on
board) prior to millivolt calibration. (Prevents offset caused by sensor bias current
through input filter). Access to the links requires that the plastic pcb covers are
removed. Observe Static Handling procedures.
There are four ranges to be calibrated; 50 ohm, 100 ohm, 250 ohm and 500 ohm.
Each range is calibrated in a similar fashion.
The parameter Input_Type must be set to the appropriate range prior to calibration.
PC3000 Installation