Honeywell SMV 3000 사용자 설명서

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SMV 3000 Transmitter User’s Manual 
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4.5
Wiring SMV 3000 Transmitter
CE Conformity Special
Conditions (Europe)
You must use shielded, twisted-pair cable such as Belden 9318 for all
signal/power wiring.
Summary
The transmitter is designed to operate in a two-wire power/current loop
with loop resistance and power supply voltage within the operating range
shown in Figure 13.
Figure 13
Operating Range for SMV 3000 Transmitters
0
10.8
16.28 20.63 25 28.3
37.0
42.4
250
450
650
800
1200
1440
Operating Voltage (Vdc)
= Operating   
    Area
NOTE: A minimum of 250 
0hms of loop resistance is 
necessary to support 
communications. Loop 
resistance equals barrier 
resistance plus wire 
resistance plus receiver 
resistance. Also 45 volt 
operation is permitted if 
not an intrinsically safe 
installation. 
Loop 
Resistance  
(ohms)
21012
You simply connect the positive (+) and negative (–) loop wires to the
positive (+) and negative (–) SIGNAL terminals on the terminal block in
the transmitter’s electronics housing shown in Figure 14.
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