THERMISTOR FUNCTION (ATEX) vacon • 41
Local contacts: https://www.danfoss.com/en/contact-us/contacts-list/
4.1.2 Hardware and connections
The thermistor (PTC) is connected between the terminals 28(TI1+) and 29(TI1-) of the OPTAF board.
The optocoupler isolates the thermistor inputs from the control board potential.
* If 230 VAC is used as control voltage from the output relays, the control circuitry must be powered with a se-
parate isolation transformer to limit short circuit current and overvoltage spikes. This is to prevent the welding
on the relay contacts. Refer to standard EN 60204-1, section 7.2.9.
The overtemperature is detected by hardware on OPTAF board. See temperature versus resistance
curve as in the figure below.
Table 12. OPTAF I/O terminals
Terminal
Parameter reference
on keypad and
NCDrive
Technical information
1SD1
+
DigIN:B.2
Isolated STO input 1 +24 V
2SD1
-Virtual GND 1
3SD2
+
DigIN:B.3
Isolated STO input 2 +24 V
4SD2
-Virtual GND 2
21
22
23
RO1/normal closed
RO1/common
RO1/normal open
DigOUT:B.1
Relay output 1 (NO/NC) *
Switching capacity 24 VDC/8 A
250 VAC/8 A
125 VDC/0.4 A
Min. switching load 5 V/10 mA
25
26
RO2/common
RO2/normal open
DigOUT:B.2
Relay output 2 (NO) *
Switching capacity 24 VDC/8 A
250 VAC/8 A
125 VDC/0.4 A
Min. switching load 5 V/10 mA
28
29
TI1+
TI1-
DigIN:B.1
Thermistor input; R
trip
> 4.0 kΩ (PTC)
max voltage = 10 V
max current = 6.7 mA
To Next Page
Loading...
