Nidec LEROY-SOMER FLSES 100 L, Руководство по пусконаладке и техническому обслуживанию

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Maintenance and service guide - LSPX-FLSPX ZONE 21 - Ex tb – LSES-FLSES ZONE 22 - Ex tc
5725 en - 2020.02 / c
5 - ELECTRICAL PARAMETRES -
LIMITING VALUES
5.1 - Limitation of disturbances caused
by starting of motors
To ensure preservation of the installation, any significant
overheating of pipework must be avoided whilst ensuring that
the protective devices do not intervene during starting.
Disturbances resulting in the operation of other equipment
connected to the same source are due to the voltage drop
caused by the current demand on starting (multiple of the
current passing through the motor at full load (about 7) see
LEROY-SOMER asynchronous motors technical catalogue).
Even though networks are increasingly capable of allowing
direct starting, current demand must be reduced for certain
installations.
Jerk-free operation and smooth starting mean that the driven
machinery will be easier to use and have a longer operating
life.
The two essential parameters for starting squirrel cage
synchronous motors are:
- starting torque
- starting current.
The starting torque and the resistive torque determine the
starting time.
Depending on the driven load, the torque and current can be
altered to match the starting options of the machine and to
match the supply options.
The five essential modes are:
- D.O.L. starting,
- star/delta starting,
- soft starting with autotransformer,
- soft starting with resistors,
- electronic starting.
Electronic starting modes control the voltage at the motor
terminals throughout the entire starting phase, giving very
gradual smooth starting.
5.2 - Supply voltage
The rated voltage is indicated on the nameplate.
5.3 - Starting times
Starting times must remain within the limits indicated below on
condition that there are 6 or less starts during one hour.
Three successive cold starts and two consecutive hot starts
are allowed.
Permissible motor starting time as a function of the ratio I
D
/ I
N
.
In the event of frequent or difficult startup conditions, equip
motors with thermal protection devices (see § 6 - USE).
5.4 - Supply with frequency inverter
See § 7.1.
25
20
15
Time (secs)
10
5
5 6 7
Id/In
8 9 10
Hot starting Cold starting
INSTALLATION AND MAINTENANCE - LSPX-FLSPX ZONE 21 - Ex tb – LSES-FLSES ZONE 22 - Ex tc
6 - USE
Thermal protection devices (see § 8) and heaters
Type
Operating
principle
Operating
curve
Switch
rating (A)
Protection provided
Mounting
Number of devices*
Thermal protection
on opening
PTO
bimetallic strip, indirectly
heated, with normally
open contact (0)
I
O TNF
T
2.5 at 250 V
with cos
j
0.4
general surveillance
for non-transient
overloads
Installed in the
control circuit
2 or 3 in series
Normally closed
thermal protection
PTF
bimetallic strip, indirectly
heated, with normally
closed (F) contact
I
F TNF
T
2.5 at 250 V
with cos
j
0.4
general surveillance
for non-transient
overloads
Installed in the
control circuit
2 or 3 in parallel