Thermistor Protection - Eaton ZEV Handbuch

05/11 MN03407008Z-DE/EN

Thermistor protection

Full motor protection can be achieved by connecting up to
six DIN 44081 and DIN 44082 PTC temperature probes with
a resistance of R F 250 O to the terminals T1-T2.
K
10000
R [O]
5000
a
3680
2000
b
1500
1000
900
800
700
600
500
-30
NAT = RTT = Rated Threshold Temperature
Figure 4 : Characteristics curve of temperature monitoring with
thermistor
a Tripping
b Reset
c Three temperature probes
d Six temperature probes
The ZEV trips at R = 3200 O g15 % and resets at
R = 1500 O + 10 %. The contacts 9596 and 9798 change
over when the unit is tripped by the signal at the thermistor
input. The thermistor tripping circuit can also be assigned to
switch over one of the contacts 05-06 or 07-08, in order to
provide a distinguished tripping indication (a fig. 7,
Page 50).
Unit description
d
c
NAT
+5 +10 +20
-20 -10
K
+30
43