Chapter 1
The SJ-EN option board is an Ethernet communication interface for the Hitachi SJ300 and L300P series of AC
Variable Frequency Inverters. The board can be installed in one of the two available option slots in the inverter.
The SJ-EN uses the open MODBUS/TCP communication protocol. It utilizes a 10Base-T physical interface with
a 10 Mbps data transfer rate. Even though the board uses the MODBUS/TCP, this does not necessarily mean that
all MODBUS services and functions are supported. Detailed description of the available functionality is
provided in Chapter 4 of this manual. The board will act as a MODBUS/TCP slave that can be read from and
written to over the Ethernet network from a MODBUS/TCP master device. It will not initiate communication
with other devices on the network. It will only respond to requests from a master device. The SJ-EN will allow a
user to control the operation of the inverter, monitor its operation, and modify parameters.
Before using this product, please read this manual and the relevant inverter manual, and be sure to follow all
safety precautions noted therein. After unpacking the SJ-EN board, carefully inspect it for any defect or damage,
and be sure all parts are present.
Carton Contents
(1) SJ-EN Ethernet Communication Interface Board
(2) Screws to secure board to inverter case (M3 x 8mm)
(1) CD-ROM containing this manual (pdf) and NetEdit3 software
WARRANTY
The warranty period under normal installation and handling conditions shall be eighteen (18) months
from the date of purchase, or twelve (12) months from the date of installation, whichever occurs first.
The warranty shall cover repair or replacement, at Hitachi’s sole discretion, of the SJ-EN Option board.
Service in the following cases, even within the warranty period, shall be to the customers account:
1. Malfunction or damage caused by misuse, modification or unauthorized repair.
2. Malfunction or damage caused by mishandling, dropping, etc., after delivery.
3. Malfunction or damage caused by fire, earthquake, flood, lightning, abnormal input voltage,
contamination, or other natural disasters.
If service is required for the product at your worksite, all expenses associated with field repair are the
purchaser’s responsibility. This warranty only covers service at Hitachi designated service facilities.
If making a warranty claims in reference to the above, please contact the distributor from whom you
purchased the SJ-EN, and provide the model number, purchase date, installation date, and description of
damage or missing components.
Page 5 of 36