Hitachi SJ7002 Series Instruction Manual page 304

B–20
Communications Reference Information
Communication
Test Mode
The communication test mode verifies that the inverter can properly send and receive data via
the RS485 serial port. Follow the steps below to perform the communication test.
1. Remove the serial cable (if present) connected to the TM2 connector block of the control
terminals, as shown below.
TM2
SP SN RP SN
Serial
communications
NOTE: It is not necessary to connect a loopback jumper. The RS485 port uses a transceiver for
communications, which already allows simultaneous transmitting and receiving.
2. Use the front panel keypad to navigate to parameter C071, Communication Speed
Selection. Change parameter C071=02 and press Store. Value 02 is the Loopback Test
option. Now the inverter is ready to conduct the loopback test.
3. Turn the inverter power OFF and then ON again to initiate the communication test. Observe
the keypad display and compare to the results shown below.
PASS
4. Press the Stop/Rest button on the keypad to return the inverter keypad/ display to normal
operation.
5. Change C071 to its original setting (default is C071=04). Otherwise, while C071=02, the
inverter will perform the communications loopback test at each powerup.
FAIL