Extreme Running Conditions - Danfoss VLT AutomationDrive FC 300 Design Manual

Product Introduction
Application example
FC
+24 V 12
+24 V 13
3 3
D IN 18
D IN 19
COM 20
D IN 27
D IN 29
D IN 32
D IN 33
D IN
37
+10 V 50
A IN
53
A IN
54
COM
55
A OUT
42
COM
39
01
02
03
04
05
06
Table 3.20 Using SLC to Set a Relay
52
®
VLT AutomationDrive FC 300 Design Guide 90-1200 kW
Parameters
Function Setting
4-30 Motor [1] Warning
Feedback Loss
Function
4-31 Motor 100 RPM
Feedback Speed
Error
4-32 Motor 5 s
Feedback Loss
Timeout
7-00 Speed PID [2] MCB 102
Feedback Source
17-11 Resolution 1024*
(PPR)
13-00 SL [1] On
Controller Mode
13-01 Start [19] Warning
Event
13-02 Stop [44] Reset
Event key
13-10 Comparat [21] Warning
or Operand no.
13-11 Comparat [1] ≈*
or Operator
13-12 Comparat 90
or Value
13-51 SL [22]
Controller Event Comparator 0
13-52 SL [32] Set
Controller Action digital out A
low
5-40 Function [80] SL digital
Relay output A
*=Default Value
Notes/Comments:
If the limit in the feedback
monitor is exceeded, Warning
90 will be issued. The SLC
monitors Warning 90 and in
the case that Warning 90
becomes TRUE, then Relay 1 is
triggered.
External equipment may then
indicate that service may be
required. If the feedback error
goes below the limit again
within 5 s, the drive continues
and the warning disappears.
But Relay 1 will still be
triggered until [Reset] on the
LCP.
MG34S202 - Rev. 2013-08-19

3.11 Extreme Running Conditions

Short Circuit (Motor Phase – Phase)
The frequency converter is protected against short circuits
by means of current measurement in each of the 3 motor
phases or in the DC link. A short circuit between 2 output
phases causes an overcurrent in the inverter. The inverter
turns off individually when the short circuit current
exceeds the permitted value (Alarm 16 Trip Lock).
To protect the frequency converter against a short circuit
at the load sharing and brake outputs, see Application Note
for FC 100, FC 200 and FC 300 Fuses and Circuit Breakers.
See certificate in .
Switching on the Output
Switching on the output between the motor and the
frequency converter is fully permitted. Switching on the
output does not damage the frequency converter, but fault
messages may appear.
Motor-Generated Over-Voltage
The voltage in the intermediate circuit is increased when
the motor acts as a generator. This occurs in the following
cases:
•
When the load generates energy, the load drives
the motor at a constant output frequency from
the frequency converter.
•
During deceleration ("ramp-down") when the
moment of inertia is high, the friction is low, and
the ramp-down time is too short for the energy
to be dissipated as a loss in the frequency
converter or motor.
•
Incorrect slip compensation setting may cause
higher DC link voltage.
•
Back-EMF from PM motor operation. If coasted at
high RPM, the PM motor back-EMF may
potentially exceed the maximum voltage
tolerance of the frequency converter and cause
damage. To help prevent this, the value of
4-19 Max Output Frequency is automatically
limited based on an internal calculation based on
the value of 1-40 Back EMF at 1000 RPM,
1-25 Motor Nominal Speed and 1-39 Motor Poles.
If it is possible that the motor may over-speed,
Danfoss recommends a brake resistor be
equipped to the frequency converter.
NOTICE
The frequency converter must be
equipped with a brake chopper.
The control unit may attempt to correct the ramp if
possible (2-17 Over-voltage Control). The inverter turns off
to protect the transistors and the intermediate circuit
capacitors when a certain voltage level is reached. See
2-10 Brake Function and 2-17 Over-voltage Control to select