ABB AC500 PLC - Connection of Resistance Thermometers in 3-wire Configuration to the Analog Inputs

Fig. 82: Connection of resistance thermometers in 2-wire configuration to the analog inputs
The following measuring ranges can be configured Ä Chapter 1.5.3.1.1.6 “Parameterization”
on page 585:
Pt100 -50 °C...+400 °C 2-wire configuration, 1
channel used
Pt1000 -50 °C...+400 °C 2-wire configuration, 1
channel used
Ni1000 -50 °C...+150 °C 2-wire configuration, 1
channel used
The function of the LEDs is described under Diagnosis and displays / Displays Ä Chapter
1.5.3.1.1.8 “State LEDs” on page 592.
The module DA501 performs a linearization of the resistance characteristic.
To avoid error messages from unused analog input channels, configure them as "unused".
Connection of Resistance Thermometers in 3-wire Configuration to the Analog Inputs
When resistance thermometers (Pt100, Pt1000, Ni1000) are used, a constant current must flow
through them to build the necessary voltage drop for the evaluation. For this, the module DA501
provides a constant current source which is multiplexed over the max. 4 analog input channels.
0
The following figure shows the connection of resistance thermometers in 3-wire configuration to
the analog inputs AI0 and AI1. Proceed with the analog inputs AI2 and AI3 in the same way.
Device Specifications
I/O Modules > Digital/Analog I/O Modules
2019/04/17 3ADR010121, 13, en_US 575