Specifications

Power Circuits Softstart UK
CAUTION
When connecting the LV-DS in inside delta configuration, always install a main contactor or shunt trip
circuit breaker.
• Inside delta installation, non-bypassed
6/T3
2/T1
5/L3
3/L2
1/L1
13
14
4/T2
KM1
KM1 F1
U1(1) U2(4)
V1(2)
V2(5)
W1(3) W2(6)
M
3
044 83.C
KM1
Main contactor
F1
Semiconductor fuses (optional)
CAUTION
When connecting the LV-DS in inside delta configuration, always install a main contactor or shunt trip
circuit breaker.
6.2. Bypass Contactor
Some LV-DS soft starters are internally bypassed and do not require an external bypass contactor.
Non-bypassed soft starters may be installed with an external bypass contactor. Select a contactor with an AC1
rating greater than or equal to the full load current rating of the connected motor.
6.3. Main Contactor
A main contactor must be installed if the LV-DS is connected to the motor in inside delta format and is optional
for in-line connection. Select a contactor with an AC3 rating greater than or equal to the full load current rating
of the connected motor.
6.4. Circuit Breaker
A shunt trip circuit breaker may be used instead of a main contactor to isolate the motor circuit in the event of a
soft starter trip. The shunt trip mechanism must be powered from the supply side of the circuit breaker or from
a separate control supply.
6.5. Power Factor Correction
If power factor correction is used, a dedicated contactor should be used to switch in the capacitors.
CAUTION
Power factor correction capacitors must be connected to the input side of the soft starter.
Connecting power factor correction capacitors to the output side will damage the soft starter.
6.6. Earth Terminals
Earth terminals are located at the back of the soft starter.
• LV-DS-0023B ~ LV-DS-0105B have one terminal on the input side (top).
• LV-DS-0145B ~ LV-DS-1000B and LV-DS-0255C ~ LV-DS-1600C have two terminals, one on the input
side (top) and one on the output side (bottom).
6.7. Power Supply Fuses
Semiconductor fuses can be used for Type 2 coordination (according to IEC 60947-4-2 standard) and to reduce
the risk of damage to SCRs from transient overload currents.
HRC fuses (such as Ferraz AJT fuses) can be used for Type 1 coordination according to IEC 60947-4-2
standard.
CAUTION
Adaptive Control controls the motor's speed profile, within the programmed time limit. This may
result in a higher level of current than traditional control methods.
For applications using Adaptive Control to soft stop the motor with stop times greater than 30 seconds, motor
branch protection should be selected as follows:
• standard HRC line fuses: minimum 150% motor full load current
• motor rated line fuses: minimum rating 100/150% motor full load current
• motor control circuit breaker minimum long time setting: 150% motor full load current
• motor control circuit breaker minimum short time setting: 400% motor full load current for 30 seconds
18/64 710-15797-00A – LV-DS User Manual