30
Principle of loop resistance
Measuring loop resistance
Rule:
No
door communication device
shall have a longer
distance from the
power supply & control unit
than
20 Ohm !
Rule:
Turn OFF 230 V / 50 Hz of the VS.
Connect a and b short circuit at the VS.
All other devices do not disturb the measuring process
and remain connected.
20 Ohm:
160 m wire length AS-VS (IS-VS) at a cross section
of 0.6 mm
300 m wire length AS-VS (IS-VS) at a cross section
of 0.8 mm
AS. Outdoor station
IS: Indoor station
VS: Power supply and control unit
Technical data
Supply voltage:
+24 V DC
±
8 % (Power supply & control unit)
24 V (a-b) / 26 V (P-b) in idle state
Dimensions (W x H x D):
58 x 129 x 21 mm
Input current
2-wire
I(a) = 2.6 mA in idle state
Max. input current:
I(a
max
) = 60 mA
input current
3-wire
I(a) = 0.4 mA, I(P) = 3.2
mA in idle state
Max. input current:
I(Pmax) = 40 mA
Protection class:
III
Admissible ambient temperature:
0 °C to 40 °C
Operation humidity:
0 to 93 % r. h., no condensation
Installation height:
Recommended 1.50 m
Cleaning
!
Avoid the penetration of water into this device!
Do not use any aggressive or abrasive cleaning supplies!
Please clean the device with a dry or slightly moist rag.
Intense dirt can be removed with a mild cleaning supply.
connect a, b
