n
n
N
bF3,
ventilation referred to zero speed
bF2,
ventilation reduced for
n < n
N
bF1, ventilation
speed-independent
t
trip
Commissioning
5–23
1070 066 028-101 (01.05) GB
5.1.16
Motor protection function
On the DM..8001 (ASM) you may alternatively choose between two motor
protection functions:
D
Connection of a temperature sensor integrated in the motor winding
head.
D
Activation of the electronic bimetal function which provides for thermal
motor protection without an integrated temperature sensor.
.
It is not possible to monitor several motors operated simultaneously at
one inverter!
Temperature sensor
A PTC temperature sensor or switch may be connected to terminal strip
X23.1/2 (cf. ”Interface conditions” manual). This component needs no pa-
rameter settings.
Bimetallic function
As in the case of a bimetallic relay, the following parameters must be
entered:
D
Rated motor current (P04)
D
Release current constant (P44)
D
Release time (P45)
.
For safety reasons, the last thermal load value of the motor remains
stored when the inverter is switched off. It will be taken as the initial
value when switched on again.
When the inverter has been switched off, it should be switched on
again while the motor is cooling down to keep identical values for the
motor temperature and the bimetal model. Do not activate enable
signal!
If the inverter remains switched off while the motor cools totally down, the
bimetal model can be reset to zero:
D
by deactivating the bimetal function via P43 and subsequent mains off, or
D
by selecting another parameter list using interface signals PL
A
, PL
B
,
PL
C
.
P43 (A-0-0043)
Activate bimetal function
factory
setting
all
DMs, DS
bF0
(0)
bF2
(2)
off
on,
n-independent,
e.g. externally
ventilated motor
on,
<n
N
reduced,
e.g. internally
ventilated motor
bF3
(3)
on,
n=0 n-related,
e.g. fan switched
off
bF1
(1)