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E-882-4-E
4. WIRING
(See the "Wiring Guidelines" in the instruction manual of the companion pulse generator.)
4.1 Field Wiring Cables
(1) Use electrostatically shielded, polyethylene insulated, vinyl sheathed control cables (CEVS, 1.25-2
mm, 2-conductor or 3-conductor), or equivalent, for input signal cables from the flowmeter.
For output signal cables, use insulated vinyl sheathed cables (CVV, CVS ... JIS C 3401).
(2) Ground the end of shield wire to "G" terminal of the instrument. At the sensor end, leave the end of
shield wire unconnected.
4.2 Wiring Connections
(1) Field wiring through a conduit is recommended.
NOTE: In routing field wiring, use a separate conduit for power cable from other signal cables to
eliminate the possibility of stray current pickup.
(2) Separate field wiring from other power lines and power circuits to minimize the possibility of inductive
interference.
(3) Using crimp-type lugs for wiring, ensure good electrical connections.
Terminals are found on the back of the instrument (Fig. 4.1).
4.3 Description of Terminal Blocks for External Connections
Terminal blocks for external connections (TB1,
TB2, and TB3) are found on the back of the
instrument as shown in Fig.4.1. Terminal identifica-
tion appears in Table 4.1 while terminal connections
appear in Table 4.2.
NOTE: TB1 and TB2 terminal numbers are
indicated on the side of terminal blocks.
TB1
TB2
1
SUP.
Flow in
12
1
SUP.
Press. in
※1
8
+
Pulse out
2
SIG.
13
2
+
9
−
3
0V
14
3
−
10
4 OUT 1/1
15
4
+
Analog out
11
5
b
Temp. in
16
5
−
12
6
B
17
6
+
Pulse out 1
13
7
A
18
+
COMM1
※
7
−
8
+
19
−
TB3
9
−
20
+
COMM2
※
1 H(+)
Power
10
+
Alarm out 21
−
N(−)
11
−
3
GND
NOTE
※
: Provided with communication interface.
※
1: With direct coupled pressure transmitter, TB2-1, (+); TB2-2 (
−
).
Fig. 4.1 Terminal Blocks for Ext. Connections
Table 4.1 Terminal Identification and Functions
TB
1
TB
2
1
2
3
TB
3
PLS OUT3
TEMP
IN
TEMP
IN
FLOW IN
0V
+
−
B
b
A
+
−
+
−
−
+
−
+
−
+
−
+
−
+
−
SIG
SUP
0V
SIG
SUP
SUP
ANA
OUT
GND
POWER
N
(
−
)
H
(
+
)
PRESS IN
PLS OUT1
COMM1
COMM2
TEMP
PLS OUT2
1/1 OUT
DENSITY
IN
Terminal Screws
(M3.5)
CAUTION
Make wiring connections upon confirma-
tion of the validity of flowmeter (pulse
generator) to receiving instrument com-
bination by their product code number,
instrument number, etc.