Hitachi MICRO-EHV+ - Page 159

Chapter 4 Installation
4 – 5
(5) Input wiring for the input terminal
Item
DC input
DC input (High speed counter)
External wirin
g
24V
0V
[0]
[2]
[3]
[C0]
[1]
[4]
[5]
[6]
Current-output-type
proximity switch
24V DC
24V
0V
[0]
[2]
[3]
[C0]
[1]
Rotary encoder
24V DC
1kΩ, 3W
NPN open collector type encoder
1
24V
3
4
15
14
C0
B
Z
24V
0V
5
0V
0
2
A
PNP open collector type encoder
NPN voltage output type encoder
1
24V
3
4
15
14
C0
A
B
Z
24V
0V
5
0V
0
2
Figure 4.5 Input wiring
(a) DC input
1] When each input and common terminal (C) are loaded with 24VDC, the input status changes to ON, and
approximately 4.8mA or 8 mA (depending on input numbers) current flow to the external input contacts.
2] For sensors such as a proximity switch and photoelectric switch, current-output-type (transistor open
collector) can be directly connected. For voltage-output-type sensors, connect them to the input terminal
after first going through the transistor.
3] Measures to prevent faulty contact in a strong electric contact
Strong electric
contact
3 W
560

Approx.
50mA
24V DC
+
0
C
The current that flows to a contact when external contacts
are closed is approximately 4.8mA or 8mA. If the use of a
strong electric contact cannot be avoided, add resistance as
shown in the diagram at left and supply sufficient current to
the contact to prevent a faulty contact.
4] Limit the wiring length within 30 m (98.43ft.).
5] Each common on the input terminal block is independent of each other. Make an external connection as
needed.