Wiring; Wiring Precautions - Mitsubishi Electric QD62 User Manual

4 SETUP AND PROCEDURE BEFORE STARTING THE OPERATION

4.4 Wiring

4.4.1 Wiring precautions

Inverter
AC
motor
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The following explains how to wire the encoder and the controller to the QD62(E/D).
In order to fully utilise the functions of the QD62(E/D) and ensure system reliability,
external wiring having a minimum of noise effect must be provided.
The precautions regarding external wiring are described below.
(1) Different terminals have been prepared for connection depending on the voltage
of the input signal. Connecting a terminal of incorrect voltage may result in
malfunction or mechanical failure.
(2) For 1-phase input, always perform pulse input wiring on the Phase A side.
(3) When pulse status noise is input, the QD62(E/D) may miscount.
(4) Provide the following measures against noise for high-speed pulse input:
(a) Always use a shielded twisted pair cable and provide grounding.
(b) Avoid placing the shielded twisted pair cables or input/output cables. Place the
cable at least 150 mm (5.9 inch) from such wires and perform wiring using the
least distance as possible.
(5) An example of wiring incorporating measures against noise is shown below:
Programmable
controller
QD62 (E/D)
Terminal block
Do not enclose solenoids and inductive loads together within the same metal conduit.
If a sufficient distance cannot be secured to isolate ducts and other wires from a high-
voltage line, use CVVS or other shielded wire for the high-voltage line.
Provide a clearance
of 150 mm (5.9 inch)
or more from I/O
wires to high voltage
equipment such as
inverters. (Also
exercise caution for
wiring inside the
panel.)
Carrier
• Grounding the shielded twisted pair cable is performed on the encoder side (relay box). (This example
shows connection with 24 V sink load.
+ 24 V
Current for the encoder
To A
To B
To QD62 (E/D)
Relay box
Encoder
To the encoder
0 V
A
B
24V
E
E
The distance between the encoder and relay box
must be short. Allowing a long distance between
the QD62 (E/D) and the encoder may cause a
voltage-drop problem. Using a tester or other
measuring device, confirm that the voltage at the
terminal block of the relay box doesn't exceed the
rated voltage when the encoder is in operation or
at standstill. If a substantial voltage drop occurs,
increase the wire size or use a 24 V DC encoder
with minimal current consumption.
The shielded wire for the encoder and shielded
twisted pair cable are connected inside the relay box .
If the shielded wire for the encoder is not grounded
inside the encoder, ground it in the relay box, as
indicated by the dotted line.
MELSEC-Q
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