Honeywell International Inc. RTU-K12 사용자 설명서

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INPUTs 
Page 13 
Digital INPUTs 
The typical connection for digital dry contacts is shown in the next figure. 
input 1+
input 1-
input  2+
input  2-
Normally closed (door)
Push Button
+12V Ground
Dry contact
Normally open (Exit)
Figure 8. Clean Contacts Connection Example 
When the cables go out-of-doors it is mandatory to use shielded cables. The 
cables’ shielding must be connected to the ground connector. 
For internal wiring without shielded cables is recommended an electrical 
environment where the cables are well separated, even at short runs, 
especially to the power cables or external cables which can be essentially 
subjected to interference or lighting. 
Use a twisted-pair cable for the contact cables. Make sure that the cables 
correspond in size to the norms indicated in. 
Max resistance = 25 Ohm 
AWG
mm2
ohm/Km
[m]
22
0,35
52
240
24
0,2
85
147
 
 
Table 3. Length of Contact Cables