Wiring Precautions - Mitsubishi Electric FR-CS82S-025 Instruction Manual

• Terminal 5 is a common terminal for the frequency setting signal input (via terminal 2 or 4). It should be protected from
external noise using a shielded or twisted cable.
 Signal inputs by contactless switches
The contact input terminals of the inverter (STF, STR, RH, RM, RL) can be controlled using a transistor instead of a contact
switch as shown below.
External signal input using transistor
2.6.4

Wiring precautions

• It is recommended to use a cable of 0.3 to 0.75 mm
• The wiring length should be 30 m at the maximum.
• Use two or more parallel micro-signal contacts or twin contacts to prevent contact faults when using contact inputs since
the control circuit input signals are micro-currents.
Micro signal contacts
• To suppress EMI, use shielded or twisted cables for the control circuit terminals and run them away from the main and
power circuits (including the 200 V relay sequence circuit). For the cables connected to the control circuit terminals,
connect their shields to the common terminal of the connected control circuit terminal. When connecting an external power
supply to terminal PC, however, connect the shield of the power supply cable to the negative side of the external power
supply. Do not directly earth (ground) the shield to the enclosure, etc.
• Always apply a voltage to the fault output terminals (A, B, C) via a relay coil, lamp, etc.
40
2. INSTALLATION AND WIRING
2.6 Control circuit
+24V
STF, etc
Inverter
SD
(sink logic)
Twin contacts
PC
STF, etc
External signal input using transistor
(source logic)
2
for the connection to the control circuit terminals.
Inverter
+24V
R