Yokogawa EJX110A - Manual (Page 32)

<6. Wiring>
6-2
IM 01C25B01-01E
6.3.4 Check Meter Connection
Available only when /AL is not specified.
Connect the check meter to the CHECK + and
– terminals. (Use hooks.)
• A 4 to 20 mA DC output signal from the CHECK
+ and – terminals.
(Note) Use a check meter whose internal resistance is 10 Ω or
less.
SUPPL Y
PULSE
CHECK ALARM
Transmitter terminal box
F0604.ai
Power supply
–
+
Check meter
Figure 6.4 Check Meter Connection
6.3.5 Status Output Connection
When option code /AL is specified, connect the
external wiring as shown in Figure 6.5.
To configure and activate the process alarm
function and status output, it is necessary to set
some parameters. Refer to each communication
manual for procedures.
SUPPL Y
PULSE
CHECK ALARM
Transmitter
terminal box
Magnetic
valve
AC power supply
External power
supply 30V DC,
120mA max
+
– 250Ω
24V DC
Use two-wire separately shielded cables.
Distributor
Shielded cable
F0605.ai
Figure 6.5 Status Output Connection
6.4 Wiring
6.4.1 Loop Configuration
Since the DPharp uses a two-wire transmission
system, signal wiring is also used as power wiring.
DC power is required for the transmitter loop. The
transmitter and distributor are connected as shown
below.
For details of the power supply voltage and load
resistance, see section 6.6; for communications line
requirements, see section 9.1.
(1) General-use Type and Flameproof Type
Hazardous Location Nonhazardous Location
Transmitter terminal box
Distributor
(Power supply unit)
Receiver
instrument
F0606.ai
SUPPL Y
PULSE
CHECK ALARM
Figure 6.6 Connection between Transmitter and
Distributor
(2) Intrinsically Safe Type
With the intrinsically safe type, a safety barrier must
be included in the loop.
Hazardous Location Nonhazardous Location
Transmitter terminal box
Distributor
(Power supply unit)
Receiver
instrument
Safety barrier
F0607.ai
SUPPL Y
PULSE
CHECK ALARM
Figure 6.7 Connection between Transmitter and
Distributor
6.4.2 Wiring Installation
(1) General-use Type and Intrinsically Safe
Type
With the cable wiring, use a metallic conduit or
waterproof glands.
• Apply a non-hardening sealant to the terminal
box connection port and to the threads on the
flexible metal conduit for waterproofing.
F0608.ai
Flexible metal conduit
Wiring metal
conduit
Tee
Drain plug
Apply a non-hardening
sealant to the threads for
waterproofing.
Figure 6.8 Typical Wiring Using Flexible Metal
Conduit