93
ETH Select [ADV: Code No. 44]: Mode of electronic thermal protection
Range: None
(Factory Default: None)
Const Torq
Vari Torq
ETH level [ADV: Code No. 45]: ETH Level
Range: 30 - 150%
(Factory Default: 150%)
Motor Type [ADV: Code No. 46]: Type of motor
Range: General
(Factory Default: General)
Special
This function is used to compensate for excessive motor heat generated during long
term low frequency operation. This is especially true if the capacity of the hoist motor is
lower than that of the inverter. To prevent the motor from overheating, the ETH level
[ADV: Code No. 45] must be set according to the provided formula.
ETH level(%) = K x (Motor rated current / Inverter rated current) x 100%
( K = 1.0 for 50Hz Input Power, K = 1.1 for 60 Hz Input Power)
Once the ETH level is found, then the Motor Type [ADV: Code No. 46] of the hoist must
be determined. There are two electronic thermal motor characteristics, one is General
pertaining to a standard AC induction motor, the other is Special for a special motor
containing a blower. Once the correct values are programmed, the drive will determine
the ETH time from a formula using M-rated cur [ADV: Code No. 31] and ETH level.
5.3.11 Stall Prevention
Stall mode [ADV: Code No. 38]: Stall prevention mode selection
Range: None
(Factory Default: None Hoist
Acc
Acc Traverse)
Steady
Acc+Steady
Dec
Acc+Dec
Dec+Steady
Acc+Dec+Steady
Stall level [ADV: Code No. 39]: Stall prevention level
Range: 30 - 150%
(Factory Default: 150%)
NOTE: DO NOT USE STALL PREVENTION ON HOIST MOTION.
GREAT CARE SHOULD BE EXERCISED WHEN SELECTING DECELERATION,
“Dec”, AS A STALL PREVENTION MODE WHEN USING A DYNAMIC BRAKING
RESISTOR.
These functions are used to prevent the traverse faults that occur due to load fluctuation
by reducing the inverter output frequency until the motor current level decreases below
Stall level [ADV: Code No. 39]. Once the motor current level satisfies the value of Stall
level, then the drive will increase its output frequency to its set point.
For more information contact: Sievert Crane and Hoist, (708) 771-1600, [email protected], www.sievertcrane.com