Connecting to plcs and other devices -4, Connecting to plcs and other devices – Hitachi X200 Series User Manual

Page 143

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Connecting to PLCs and Other Devices

Hitachi inverters (drives) are useful in many types of applications. During installation,

the inverter keypad (or other programming device) will facilitate the initial
configuration. After installation, the inverter will generally receive its control

commands through the control logic connector or serial interface from another

controlling device. In a simple application such as single-conveyor speed control, a
Run/Stop switch and potentiometer will give the operator all the required control. In a

sophisticated application, you may have a

programmable logic controller

(PLC) as the

system controller, with several connections to the inverter.

It is not possible to cover all the possible types of application in this manual. It will be

necessary for you to know the electrical characteristics of the devices you want to

connect to the inverter. Then, this section and the following sections on I/O terminal
functions can help you quickly and safely connect those devices to the inverter.

CAUTION: It is possible to damage the inverter or other devices if your application
exceeds the maximum current or voltage characteristics of a connection point.

The connections between the inverter and
other devices rely on the electrical

input/output characteristics at both ends of

each connection, shown in the diagram to the
right. The inverter’s configurable inputs

accept either a sourcing or sinking output

from an external device (such as PLC). This
chapter shows the inverter’s internal

electrical component(s) at each I/O terminal.

In some cases, you will need to insert a power
source in the interface wiring.

In order to avoid equipment damage and get

your application running smoothly, we
recommend drawing a schematic of each

connection between the inverter and the

other device. Include the internal components
of each device in the schematic, so that it

makes a complete circuit loop.

After making the schematic, then:

1.

Verify that the current and voltage for

each connection is within the operating

limits of each device.

2.

Make sure that the logic sense (active high or active low) of any ON/OFF connection

is correct.

3.

Check the zero and span (curve end points) for analog connections, and be sure the

scale factor from input to output is correct.

4.

Understand what will happen at the system level if any particular device suddenly

loses power, or powers up after other devices.

Other device

Input

circuit

Output

circuit

X200 inverter

Input

circuit

Output

circuit

signal
return

signal
return

Other device

X200 inverter

Input

circuits

P24

1

2

3

4

5

L

24V

+ -

GND

44

Operatio

ns and

Monitori

ng

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