YOKOGAWA YTA Series - Page 20

5-2
IM 01C50C05-01EN
F0502.ai
<Hazardous location> ← → <Nonhazardous location>
Input signal
(Thermocouples,
RTDs,DC millivolts,etc)
Output
signal
Distributor
(Power supply unit) Receiver
+
–
Safety
barrier
Figure5.2 LoopConstruction(forIntrinsicallySafeType)
(Ω)
Power supply voltage E (V DC)
600
250
R
8.0
13.8
21.8
External
load
resistance
E-8
0.0236
R=
Digital
Communication
range
F0503.ai
35.0
Figure 5.3 RelationbetweenPowerSupplyVoltageandLoadResistance
Note: For intrinsic safe explosion protected type units, the internal
resistance of the safety barrier is also included in the load resistance.