Yokogawa JUXTA VJCE - Manual (Page 6)

6
All Rights Reserved. Copyright © 1999, Yokogawa M&C Corporation IM 77J01C51-01E 2nd Edition July 23,2004-00
4. EXTERNAL WIRING
4.1 Field Side Wiring and Wiring of Power Supply and Ground
Flexible twisted cable and good contact of durable round crimp-on terminals are recommended to use.
0.75 mm 2
0.9 mm 2
M3.5 3.7 or more 6.9 or less About 19 3.2 or more
1.25 mm 2
2.0 mm 2
Cross sectional
area
Screw
л D1
Hole dia.
(mm)
A
Terminal out dia.
(mm)
L
Terminal length
(mm)
øD2
Insulation coating
(mm)
L
л D1
A
л D2
4.1.1 Signal cable
Nominal cross-sectional area of conductor: 0.75 to 2 mm 2
Example of suitable cable: Vinyl code (VSF) twisted cable (JIS C3306)
4.1.2 Power cable
Nominal cross-sectional area of conductor: 1.25 to 2 mm 2
Example of suitable cable: 600V vinyl code (IV) twisted cable (JIS C3307), Vinyl insulated cable (KIV) (JIS C3316)
4.1.3 Ground cable
Nominal cross-sectional area of conductor: 2 mm 2
Example of suitable cable: 600 V vinyl code (IV) twisted cable (JIS C3307), Vinyl insulated cable (KIV) (JIS C3316)
4.2 Field Side Input/Output Terminals, Piping and System Side Wiring
Assignment of Input/Output Terminals on and after page 7 shows relation between VJCE field side input/output ter-
minals and signal conditioner input /output signal at the terminals. (Refer to the assignment for the model code to be
used for wiring.) Field side input/output terminals are M3.5 screws. Exclusive cable is used for connection between
VJCE and VM1, PM1 cards. Connect input air pressure signal of VJF1 to connecting hole of front face of signal con-
ditioner directly. Connect power and ground cables to power terminals of VJCE. Power would internally be distributed
to respective signal conditioners.
WARNING
It is recommended that CT protector (CTG-5) be attached to the current input terminals connected to the
secondary side of the CT when mouning VJB1 (CT transmitter) on VJCE. Since a high potential
develops over the secondary side, the CT may burn and break if you unplug the VJB1 from the VJCE
while the VJB1 is turned on and it has no CT protector.
IMPORTANT
● Ensure the followings before turning on the power. Use of signal conditioners of VJ series ignoring
the specifications may cause overheating or damage to VJCE-01A and signal conditioners.
· Power supply voltage and input signal value applied to VJCE-01A and signal conditioners should
meet the required specifications.
· The external wiring to the terminals is as specifications.
● Do not operate the product in the presece of flammable or explosive gases or vapors. To do so is
highly dangerous.
● Many semi-conductor integrated circuit parts are used for signal conditioners. Take care of static
electricity trouble at the maintenance or change of setting for the signal conditioners.
● The grounding resistance must be 100
Ω
(JIS Class D grounding). The length and thickness of the
grounding cable should be as short and thick as possible. Directly connect the lead from the ground
terminal of the product to the ground. Do not carry out daisy-chained inter-ground terminal wiring.