YOKOGAWA EJX Series - 5.5 Grounding; 5.6 Power Supply Voltage and Load Resistance

  <5.Wiring>
34
IM01C25A01-01E
5.5 Grounding
Groundingisalwaysrequiredfortheproperoperationof
transmitters.Followthedomesticelectricalrequirements
asregulatedineachcountry.Foratransmitterwitha
built-inlightningprotector,groundingshouldsatisfy
groundresistanceof10Ωorless.
Groundterminalsarelocatedontheinsideandoutsideof
theterminalbox.Eitheroftheseterminalsmaybeused.
Ground terminal
(inside)
Ground terminal
(outside)
F0525.ai
SUPPLY
PULSE
CHECK
ALARM
Figure5.14 GroundTerminals
5.6 PowerSupplyVoltageand
LoadResistance
Whenconguringtheloop,makesurethattheexternal
loadresistanceiswithintherangeinthegurebelow.
(Note) Incaseofanintrinsicallysafetransmitter,externalload
resistanceincludessafetybarrierresistance.
600
250
0 10.5 16.6 25.2 42
External
load
resistance
R (Ω)
Power supply voltage E (V DC)
F0526.ai
Communication
applicable range
BRAIN and HART
R=
E–10.5
0.0244
Figure5.15 RelationshipbetweenPowerSupply
VoltageandExternalLoadResistance