50020 Electrical Control Wiring

The maximum operating temp of a controller is

140*F

Devices that create heat, such as transformers, drives, and power supplies are mounted at the ___ of the enclosure to avoid overheating PLCs

Top

VFD

A variable frequency drive is used to operate an AC motor at varying speeds, should be installed at top of enclosure

Grounding Circuit

The PLC must be connected to ground

I/O wiring circuit

onnects field input devices (such as switches and sensors) and output devices (such as actuators and relays) to controller modules, routed separately from high-voltage power lines to prevent electrical noise.

Brick Style PLC Grounding

Usually grounded at a ground terminal on PLC device

Chassis Style PLC Grounding

Chassis style have a chassis into which a number of modules are inserted. Usually grounded at chassis

Wiring AC to Brick Style

Wiring AC to Chassis Style

Wiring DC to Brick Style

Wiring DC to Chassis Style

MCR Circuit Test

Discrete Input and Output Devices

Wired to PLCs to provide on/off functions

Sinking Input Switching

Activating the input device will cause current to flow from the input device to module. Pictured chassis style DC

Sourcing Input Switching

Causes current to flow from input module to device

pictured brick style DC

Bleeder resistor

Used to prevent current leakage from other devices like proximity sensors

VFD connected to 3 phase motor