Hitachi SJ700 Series Manual page 18

PROTECTIVE FUNCTIONS
Name
The inverter output was short-circuited, or the motor shaft is locked or has a
heavy load. These conditions cause excessive current for the inverter, so the
Over-current protection
inverter output is turned off.
When a motor overload is detected by the electronic thermal function, the inverter trips and turns off its out-
Overload protection(*1)
put.
When the regenerative braking resistor exceeds the usage time allowance or an over-voltage caused by the
Braking resistor
stop of the BRD function is detected, the inverter trips and turns off its output.
overload protection
When the DC bus voltage exceeds a threshold, due to regenerative energy from the motor, the inverter trips
Over-voltage protection
and turns off its output.
When the built-in EEPROM memory has problems due to noise or excessive temperature, the inverter trips
EEPROM error(*2)
and turns off its output.
A decrease of internal DC bus voltage below a threshold results in a control circuit fault. This condition can
Under-voltage error
also generate excessive motor heat or cause low torque. The inverter trips and turns off its output.
If a strong source of electrical interference is close to the inverter or abnormal operations occur in the
CT(Current transformer) error
built-in CT, the inverter trips and turns off its output.
CPU error
When a malfunction in the built-in CPU has occurred, the inverter trips and turns off its output.
When a signal to an intelligent input terminal configured as EXT has occurred, the inverter trips and turns
External trip
off its output.
An error occurs when power is cycled while the inverter is in RUN mode if the Unattended Start Protection
USP error
(USP) is enabled. The inverter trips and does not go into RUN mode until the error is cleared.
The inverter is protected by the detection of ground faults between the inverter output and the motor during
Ground fault
power-up tests. This feature protects the inverter only.
When the input voltage is higher than the specified value, it is detected 60 seconds after power-up and the
Input over-voltage protection
inverter trips and turns of its output.
When power is cut for more than 15ms, the inverter trips and turns off its output. If power failure continues,
Instantaneous power failure
the error will be cleared. The inverter restarts if it is in RUN mode when power is cycled.
Temperature error due to low
The inverter will display the error code shown on the right if the lowering of cooling-fan speed is detected at
cooling-fan speed
the occurrence of the temperature error described below.
When the inverter internal temperature is higher than the specified value, the thermal sensor in the inverter
Inverter thermal trip
module detects the higher temperature of the power devices and trips, turning off the inverter output.
Gate array error Communication error has occurred between CPU and gate array.
One of three lines of 3-phase power supply is missing.
Phase loss detection
The inverter will trip if the gate array cannot confirm the on/off state of IGBT because of a malfunction due
Main circuit error (*3)
to noise or damage to the main circuit element.
When an instantaneous over-current has occurred, the inverter trips and turns off its output to protect main
IGBT error
circuit element.
When the thermistor inside the motor detects temperature higher than the specified value, the inverter trips
Thermistor error
and turns off its output.
The inverter turns off its output when it can not detect whether the braking is ON or OFF within waiting time
Braking error
set at b024 after it has released the brake. (When braking is enabled at b120)
If the EMR signal (on three terminals) is turned on when the slide switch (SW1) on the logic board is set to
Emergency stop (*4)
ON, the inverter hardware will shut off the inverter output and display the error code shown on the right.
If overload occurs during the motor operation at a very low speed at 0.2 Hz or less, the electronic thermal protection
circuit in the inverter will detect the overload and shut off the inverter output. (2nd electronic thermal control)
Low-speed overload protection
(Note that a high frequency may be recorded as the error history data.)
If timeout occurs because of line disconnection during the communication in Modbus-RTU mode, the inverter
Modbus communication error
will display the error code shown on the right. (The inverter will trip according to the setting of "C076".)
Due to insufficient voltage, the inverter has turned off its output and been trying to
Out of operation due
to under-voltage restart. If it fails to restart, it goes into the under-voltage error.
Easy sequence function Error
Error indications by protective functions with the easy sequence function used.
Expansion card 1 connection error
An error has been detected in an expansion card or at its connecting terminals.
Expansion card 2 connection error
*1: Reset operation is acceptable 10 seconds after the trip.
*2: Check the parameters when EEPROM error occurs.
*3: The inverter will not accept reset commands input via the RS terminal or entered by the STOP/RESET key. Therefore, turn off the inverter power.
*4: The inverter will not accept the reset command entered from the digital operator. Therefore, reset the inverter by turning on the RS terminal.
Status Display
〈 〉
Code
How to access the details about the present fault
〈
Error code Status at trip point
17
Description Code Description
Reset Deceleration
0 2
1 Stop 3 Constant Speed
Output frequency Motor current
at trip point at trip point
Cause(s)
While at constant speed
During deceleration
During acceleration
Others
Code Description
Acceleration
4
5 f0 Stop
〉
Voltage between
−
P(+) and N( ) at trip point
Display
on digital
operator
〜
〜
Code Description Code
Starting Overload Restriction
6 8
7 DB 9 Forcible or servo-on
Cumulative inverter Cumulative power-on
RUN time at trip point time at trip point
Display on remote
operator/copy unit
ERR1****
OC.Drive
OC.Decel
OC.Accel
Over.C
Over.L
OL.BRD
Over.V
EEPROM
Under.V
CT
CPU
EXTERNAL
USP
GND.Flt.
OV.SRC
Inst.P-F
OH.stFAN
OH FIN
GA
PH.Fail
Main.Cir
IGBT
TH
BRAKE
EMR
OL-LowSP
NET.ERR
UV.WAIT
PRG.CMD
PRG.NST
PRG.ERR1
OP1-0 OP1-9
〜
OP2-0 OP2-9
〜
Description