YASKAWA E7U Programming Manual page 102

Modbus Self-Diagnosis
The Drive has a built-in function for self-diagnosing the operations of serial communication interface circuits. The
self-diagnosis function connects the communication parts of the send and receive terminals, receives the data sent by the
Drive, and checks if communication is being performed normally.
Perform the self-diagnosis function using the following procedure.
1. Turn ON the power supply to the Drive, and set parameter H1-05 (Terminal S7 Function Selection) to 67 (Comm Test
Mode).
2. Turn OFF the power supply to the Drive.
3. Perform wiring according to the following diagram while the power supply is turned OFF.
4. Turn ON the terminating resistance. (Turn ON pin 1 on DIP switch 1.)
5. Turn ON the power supply to the Drive again.
6. During normal self-diagnostic operation, the Digital Operator displays the frequency reference value. If an error occurs, a
CE (Modbus communication error) alarm will be displayed on the Digital Operator, the fault contact output will be turned
ON, and the Drive operation ready signal will be turned OFF.
H5-01 Drive Node Address
Setting Range: 0 to 20 (Hex)
Factory Default: 1F
In order for a master to be able to communicate with the Drive using serial communications, the Drive must have a unique
node address. The Drive is given a node address if H5-01 ≠ 0. The node addresses do not have to be assigned in sequential
order but they must be unique, i.e. no two Drives on the same serial network can be assigned the same address. After setting
the Drive address with the H5-01 parameter, the power to the Drive must be cycled for the addressing to take effect.
Leaving H5-01= 0 will disable responses to MEMOBUS communications.
H5-02 Communications Speed Selection
Setting
0 1200 Baud
1 2400 Baud
2 4800 Baud (Standard for APOGEE)
3 9600 Baud (factory default) (Standard for Metasys)
4 19200 Baud
Fig. 70 Communication Terminal Connection for Self -Diagnosis Function
}
MODBUS
Description
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0 to FF 0 to 63
N2
1F 1F
Programming 96
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P1