Hitachi Sj7002 Owners Manual

Maintenance and Inspection
Troubleshooting
and Maintenance
6–24
To install the new fan(s):
1. Slide the fan(s) into the mounting locations in the mounting 
plate. To ensure the correct airflow, be sure that the label on 
each fan faces toward the vent openings (top of inverter).
2. Connect the fan wiring to terminals J21 or J22 (depending on 
the inverter model) on the main circuit board.
3. Put the mounting plate in position on the top of the inverter. 
Press downward on the fan units  until the...

SJ7002 Inverter
Troubleshooting
and Maintenance
6–25
General Inverter 
Electrical 
MeasurementsThe following table specifies how to measure key  system electrical parameters. The diagrams 
on the next page show inverter-motor systems  and the location of measurement points for these 
parameters.
Note 1: Use a meter indicating  a fundamental wave effective value for voltage, and meters 
indicating total effective va lues for current and power.
Note 2: The inverter output has a  distorted waveform, and...

Maintenance and Inspection
Troubleshooting
and Maintenance
6–26
The figure below shows measurement locations fo r voltage, current, and power measurements 
listed in the table on the previous page. The voltage to be measured is the fundamental wave 
effective voltage. The power to be measured is the total effective power.
Inverter Output 
Voltage Measure-
ment TechniquesTaking voltage measurements around drives equi pment requires the right equipment and a safe 
approach. You are working with high...

SJ7002 Inverter
Troubleshooting
and Maintenance
6–27
IGBT Test MethodThe following procedure will check the power mo dule, including inverter transistors (IGBTs), 
IPM, diodes, and thyrister unt il replacement of inverter (1,000,000 start/stop cycles):
1. Disconnect input power to te rminals [R, S, and T] and mo tor terminals [U, V, and W]. 
2. Disconnect any wires from  terminals [P] and [RB] for regenerative braking.
3. Use a Digital Volt Meter (DVM) and set it fo r 1 ohm resistance range. You can...

Maintenance and Inspection
Troubleshooting
and Maintenance
6–28
Dynamic  Braking
(0.4kW–11kW)
TR7RB P Non-conducting
P RB Conducting
RB N Non-conducting
N RB Non-conducting
Circuit TypeDVM  ProbeMeasured Value+–

Phone: 800.894.0412   

SJ7002 Inverter
Troubleshooting
and Maintenance
6–29
Warranty
Warranty Terms
The warranty period under normal installation and  handling conditions shall be two (2) 
years from the date of manufacture (“DATE” on product nameplate), or one (1) year 
from the date of installation, whichever occurs  first. The warranty shall cover the repair 
or replacement, at Hitachis sole discretion , of ONLY the inverter that was installed.
1. Service in the following cases, even within  the warranty period, shall be...

Phone: 800.894.0412   

Glossary and 
Bibliography
In This Appendix....page
— Glossary............................................................................................   2
— Bibliography......................................................................................   6
A

Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: [email protected]  

Glossary
Appendix A
A–2
Glossary
Ambient
Te m p e r a t u r eThe air temperature in the chamber containing a powered electronic unit. A unit’s heat sinks 
rely on a lower ambient temperature in order to dissipate heat away fro m sensitive electronics.
Arrival FrequencyThe arrival frequency refers to the set output frequency of the inverter for the constant speed 
setting. The arrival frequency feature turns ON  an output when the inverter reaches the set 
constant speed. The inverter ha s various arrival...

SJ7002 Inverter
Appendix A
A–3
DiodeA semiconductor device that has a voltage-current characteristic that allows current to flow 
only in one direction, with negligible leakage current in th e reverse direction. See also rectifier.
Duty Cycle1. The percent of time a square wave of fixed frequency is ON (high) versus OFF (low).  2. The 
ratio of operating time of a motor, braking resi stor, etc. to its resting time. This parameter 
usually is specified in association with the allowable thermal rise for...