Hitachi L200 Manual Do Utilizador

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Connecting to PLCs and Other Devices
Oper
ations
and Monitor
ing
4–4
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 configura-
tion. 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 poten-
tiometer 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 a PLC). 
This chapter shows the inverter’s internal 
electrical component(s) at each I/O termi-
nal. 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 compo-
nents 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
L200 Inverter
Input
circuit
Output
circuit
PCS
1
2
3
4
5
L
Input 
circuits
+ –
signal
signal
return
return
PLC
Inverter
24V
GND
+Com