5.2 Combination with Other Components using STO
e
3
0
b
a
9
6
7
.1
3
Digital input
PTC
sensor
Non-hazardous area
Hazardous
area
X44/
PTC Thermistor Card
MCB 112
1 2 3 4 5 6 7 8 9 10 1112
Safety device
Manual restart
SIL 2
Safe AND input
Safe output
S
a
fe
i
n
p
u
t
DI
DI
STO
Par. 5-19
Terminal 37 Safe Stop
12 13 18 19 27 29 32 33 20 37
e.g. Par 5-15
Illustration 10: More Safety Devices in Combination with STO and VLT
®
PTC Thermistor Card MCB 112
Table 4: Programming Example 2
Option number
Option name
Description
Parameter 5-19 Terminal 37 Safe Stop
[6]
PTC 1 & Relay
alarm
If the motor temperature is too high, or if a PTC failure occurs, the MCB 112 activates the
STO of the drive. Terminal 37 goes low (active), and digital input 33 goes high (active).
This parameter decides the consequence of the Safe Torque Off (STO). With this selec-
tion, the drive coasts and the LCP shows
alarm 71, PTC 1 safe stop
. Reset the drive man-
ually from LCP, digital input, or fieldbus when the conditions of the PTC are acceptable
again (motor temperature has dropped). An emergency stop can also activate STO. Ter-
minal 37 goes low (active), but MCB 112 X44/10 does not trigger digital input 33 as the
MCB 112 did not have to activate the STO. Therefore, digital input 33 remians high (inac-
tive).
Parameter 5-15 Terminal 33 Digital Input
[80]
PTC card 1
Connects the digital input of terminal 33 to the MCB 112, which enables the MCB 112 to
indicate when STO has been activated from here.
Alternatively,
parameter 5-19 Terminal 37 Safe Stop
could be set to
[7] PTC 1 & relay warning
. Selecting this option causes an automat-
ic restart when the conditions of the PTC circuit and/or emergency stop circuit have returned to normal. The selection depends on
customer demands. Also, the setting of
parameter 5-19 Terminal 37 Safe Stop
could be
[8] PTC 1 & relay A/W
or
[9] PTC 1 & relay W/A
,
which is a combination of alarms and warnings. The selection depends on customer demands.
N O T I C E
Selections
[4] PTC 1 alarm
to
[9] PTC 1 & relay W/A
in
parameter 5-19 Terminal 37 Safe Stop
are only visible if the MCB 112 is plugged
into the B-option slot.
AQ267038105120en-000101 / 130R0104 | 25
Danfoss A/S © 2022.08
Application Examples
VLT® PTC Thermistor Card MCB 112
Operating Guide
