User’s
Manual
IM 77J01H07-01E
Model VJH7
Isolator (Multi-function)
(Isolated Single-output and
Isolated Dual-output Types)
1. CAUTIONARY NOTES FOR SAFE
USE OF THE PRODUCT
For the correct use of this product, read through this manual before
use. The following safety symbol is indicated on the product to ensure safe use.
CAUTION
If this symbol is indicated on the product, the operator
should refer to the explanation given in the instruction
manual in order to avoid personnel injury or death to either
themselves or other personnel, and/or damage to the instrument. The manual describes the special care the operator
should exercise to avoid shock or other dangers that may result in injury or loss of life.
The following symbol marks are used only in this manual.
IMPORTANT
Indicates that operating the hardware or software in a particular manner may damage it or result in a system failure.
NOTE
Draws attention to information that is essential for understanding the operations and/or features of the product.
4. MOUNTING METHODS
4.1 Wall Mounting
Loosen the main unit-fixing screw of the isolator to disconnect the
main unit from the socket. Next, anchor the socket onto the wall
with screws. Then, plug the main unit into the socket and secure
the main unit with the main unit-fixing screw.
Socket
Threaded hole for
fixing the main unit
Main unit
Main
unit-fixing
screw
<Mounting Dimensions>
29.5 or more
22±0.2
2-M4 or 2-ø4.5 or more
Unit: mm
Mounting
screws
2. CHECKING PRODUCT SPECIFICATIONS AND THE CONTENTS
OF PACKING
(1) Model Number and Specification Check
Check that the model number and specifications shown on the
nameplate attached on the side of the product are as ordered.
(2) Contents of the Packing
Check that the packing contains the following items:
● VJH7 main unit, 1
● Instruction Manual (IM 77J1H07-01E), 1
Accessories:
● Tag number label, 1
● Renge label, 1
● Shunt registor (for specification of current input), 1
3. GENERAL
This plug-in isolator, which belongs to the JUXTA series of signal
conditioners, receives DC current or voltage signals and converts
them to pairs of isolated DC voltage or current signals.
• Output-2 signal is selectable from a DC voltage signal, DC
current signal, communication function (RS-485), and alarm
output (two relay contacts).
Keep this manual in a safe place.
59±0.3
Fig. 4.1
4.2 DIN Rail Mounting
Locate the isolator so that the DIN rail fits into the upper part of
the DIN-rail groove at the rear of the socket, and fasten the socket
using the slide lock at the lower part of the socket.
DIN rail
VIEW A
Fig. 4.2
VIEW A (Rear of socket)
DIN rail
Slide lock
Network Solutions Business Divisiion
2-9-32, Naka-cho Musashino-shi, Tokyo 180-8750 Japan
Phone: +81-422-52-7179 Facsimile: +81-422-52-6793
IM 77J01H07-01E
1st Edition Nov. 1999
2nd Edition June 2004
2
4.3 Mounting Using a Multi-mounting Base
For mounting using a multi-mounting base, see the Instruction
Manual for VJCE (VJ Mounting Base).
4.4 Using Ducts
Wiring ducts should be installed at least 30 mm away from the top
or bottom of the main unit.
4.5 I
n case of top-and-bottom close mounting
Transmitter should be mounted horizontally with its top and bottom slits being vertical. The top and bottom slits should not be
covered.
The area for wiring is required above and below the transmitter
(the area with slant lines).
40 or more40 or more
ALM1
ALM1
ALM1
ALM2
ALM2
29.5 or more
ALM1
ALM1
ALM2
ALM2
(72)
(72)
(29.5)
78 or more
150 or more
ALM2
ALM1
ALM2
• For mounting, use M3 screws and crimp-on terminals with insulating sleeves appropriate for the wires used.
Tool of the crimp-on terminals to be used should be appropriate for the crimp-on terminals.
• Mount a breaker on the external place.
Mount a switch or 5A circuit breaker on the place near by the
instrument, within operator’s reach. And attach the indication
that it is for disconnecting the instrument.
Input signal
Analog input
+
1
R
-
3
R: 100 Ω
Externally
connected for
current input
Shunt resistor
(Externally connected
for current input)
Output-2 signal
ALM1
COM
ALM2
RS-485
communication
B+
2
A-
5
6
COM
3 2
56
1011
1
4
789
Analog output
+
2
-
5
Output-1 signal
Analog output
+
7
-
9
Alarm output
2
5
6
Fig. 4.3
5. INSTALLATION LOCATION
• For installation, avoid any location where the product may be
subject to vibrations, corrosive gases, or large amounts of
dust, or where the product is exposed to water, oil, solvents,
direct sunlight, radioactive rays, or strong electric or magnetic
fields.
• If there is a possibility that lightning could induce a high surge
voltage on the power and signal lines, provide lightning arresters on the line between the field instrument and indoor instrument in order to protect the product. Install a dedicated arrester on the field side and another on the indoor side.
6. EXTERNAL WIRING
WARNING
Turn OFF the power supply and make sure that none of the
cables are not in the hot-line state before carrying out the
wiring to avoid the possibility of electric shock.
Wires are connected to the terminals of the isolator’s socket. M3
screw terminals are provided for the connection of external signals.
Attach a crimp-on lug to each wire for connection to the terminals.
• Recommended cables: A nominal cross-sectional area of 0.5
mm2 or thicker for signal cables, and that of 1.25 mm2 or
thicker for power cables, and shielded twisted-pair cables
(AWG24) for communication wiring cables.
Power supply
L+
10
N-
11
GND
8
Fig. 6.1
● Keep all sources of noise away from the power and sig-
nal cables. Otherwise, accuracy cannot be assured.
● Provide grounding to a grounding resistance of 100 ⍀.
The length of the grounding cable should be 20 m or
less. Directly connect the lead from the ground terminal
(terminal no. 8) of the isolator to the ground. Do not
carry out daisy-chained inter-ground terminal wiring.
● Direct Current
●
“Overvoltage category (Installation category)” describes
a number which defines a transient overvoltage condition. It implies the regulation for impulse withstand voltage. “II” applies to electrical equipment which is supplied from the fixed installation like distribution board.
●
“Pollution degree” describes the degree to which a solid,
liquid, or gas which deteriorates dielectric strength or
surface resistivity is adhering. “2” applies to normal indoor atmosphere. Normally, only non-conductive pollution occurs. Occasionally, however, temporary conductivity caused by condensation must be expected.
● Rated fuse of 125VDC, 1A is stored. However, opera-
tors can not replace the fuse.
All Rights Reserved. Copyright © 1999, Y okogawa M&C Corporation IM 77J01H07-01E 3rd Edition Mar.31,1997-00