Hitachi DSP-160V6WN User Manual

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9. MAINTAINING THE DSP [How to Service the DSP Air Compressor]
① Checking the operating temperature
The motor coil has a specified maximum allowable
temperature rise of 100℃ (212℉), based on an ambi-
ent temperature off 40℃ (104℉).
If the motor is unusually hot during normal operation,
regardless of the specified temperature rise, investi-
gate the cause of the excessive heat utilizing the
Motor Diagnostics and Troubleshooting chart
below.
② Cleaning
Clean the motor periodically to prevent dust particles
from accumulating inside and outside of the motor.
When servicing the DSP, measure the insulation
resistance of the motor coil with a 500V megohmme-
ter and verify that the insulation resistance is 1MΩ
or more.
③ Disassembling
In a severe environment (dirty, corrosive, high dust or
high powder), disassemble and service the motor
every two years. In a normal environment, disassem-
ble and service the motor every four years. For
the most common motor problems, see the Motor
Diagnostic and Troubleshooting chart below.
If the problem cannot be solved with the chart, con-
sult the local Hitachi distributor.
Motor Diagnostics and Troubleshooting
Phenomenon
Cause
Excessive Sound Excessive Rotation Excessive Vibration
Heated
Thermal Relay Tripped breaker Tripped Electric Leak Low Insulation Resistance
Corrective Action
Frame Bearing
Installation
Loose botls
○◎○
Retighten the bolts.
Wiring
Poor gounding
◎
Ground properly.
Inadequate breaker capacity
○
NOTE3
◎
Replace with properly specified capacity breaker.
Broken wires
○
Install new wires.
Failed starter and switch contact
○
○
NOTE3
Check the contacts and replace if necessary.
Environment
Dust accumulation reduced cooling performance
○
Properly clean motor.
Excessive ambient operating temperature
◎○◎
Improve the room ventilation or contact the local Hitachi distributor.
High humidity
◎
Contact the local Hitachi distributor.
Large external vibration/shock
◎
Take vibration and shock measurements.
Power Supply
Phase-lacking operation
◎◎○◎ ◎○
Check the wire thickness and length and contact the
local power utilities company.
Widely dropped voltage
○○◎◎
Fluctuating voltage
○○○○
Contact the local power utilities company.
Load
Overload
○◎◎○
Check the DSP capacity control system.
Thrust force by the machine
○○◎
Center the shaft.
Excessive bearing noise NOTE 2
◎◎◎○
Contact the local Hitachi distributor.
Burnt motor coil NOTE 2
○○ ○ ◎◎◎○
Contact the local Hitachi distributor.
NOTES:
1. ◎ : Close relationship between the cause and type of problem, ○ : relationship between the cause and type of problem.
2. Detect the fundamental cause of the problem and take corrective action.
3. Breaker, switch and starter are hot.
11
Motor - (Servicing)

Hitachi DSP-160V6WN Specifications

General

Brand	Hitachi
Model	DSP-160V6WN
Category	Air Compressor
Language	English