ABB AC500 V3 Hardware Manual page 353

Terminal
12
13
14
15
16
17
18
19
20
The internal power supply voltage for the module's circuitry is carried out via the I/O bus
(provided by a communication interface module or a CPU). Thus, the current consumption from
24 V DC power supply at the terminals L+/UP and M/ZP of the CPU/communication interface
module increases by 10 mA per AI561.
The external power supply connection is carried out via the L+ (+24 V DC) and the M (0 V DC)
terminals. The M terminal is interconnected to the M/ZP terminal of the CPU/communication
interface module.
The module provides several diagnosis functions
on page 356.
The following figure is an example of the internal construction of the analog input AI0. The
analog inputs AI1...AI3 are designed in the same way.
2022/01/31
Signal
I3-
---
---
---
---
---
SG
L+
M
NOTICE!
Risk of imprecise and faulty measurements!
Analog signals may be distorted seriously by external electromagnetic influ-
ences.
Use shielded wires when wiring analog signal sources. The cable shield must
be grounded at both ends of the cable. Provide a potential equalisation of a
low resistance to avoid high potential differences between different parts of the
plant.
NOTICE!
Risk of damaging the PLC modules!
The PLC modules must not be removed while the plant is connected to a power
supply.
Make sure that all voltage sources (supply and process voltage) are switched
off before you
– connect or disconnect any signal or terminal block
– remove or replace a module.
NOTICE!
Risk of damaging the PLC modules!
Overvoltages and short circuits might damage the PLC modules.
– Make sure that all voltage sources (supply voltage and process supply
voltage) are switched off before you begin with operations on the system.
– Never connect any voltages or signals to reserved terminals (marked with
---). Reserved terminals may carry internal voltages.
3ADR010278, 3, en_US
I/O modules > Analog I/O modules
Description
Negative pole of input signal 3
Reserved
Reserved
Reserved
Reserved
Reserved
Shield grounding
Process voltage L+ (24 V DC)
Process voltage M (0 V DC)
Ä Chapter 1.6.2.1.1.6 "Diagnosis"
Device specifications
353