User's Manual
MS3707G Slim Plug-In Distributor with Isolated Single/Dual Output for Level Gauges
Rev. 1.20
3
5. External Dimensions & Terminal Assignments
ZERO Trimmer for Output 2
SPAN Trimmer for Output 2
Rotary Switch for rough SPAN adjustment
Transmitter Power Switch
ZERO Trimmer
SPAN Trimmer
Screw hole for
wall mounting
Screw hole for wall mounting
Fixing screw
6. Terminal Connection Diagram
When used as a distributor: When used as an isolator:
(Ex switch: ON) (Ex switch: OFF)
Terminal
No.
Terminal
No.
Note: For the single output model, the OUTPUT2 shown should be
interpreted as N.C.
When using the instrument as an isolator, be sure to turn off the
transmitter power switch (see below).
Toggle Switch
Function
Distributor
Isolator
Transmitter
Power
Ex Switch
* Switch lamp is on.
* Switch lamp is off.
If the transmitter power switch remains on, the following incidents
may occur.
1. If terminals #9 and #10 are connected, the 24VDC power will be
short-circuited to the ground through the internal input resistor
(250
Ω
). This may cause the resistor to burn out.
2. If terminals #9 and #11 are connected, the 24VDC power will be
short-circuited directly to the ground. This may cause damage to
the power circuit.
3. If terminal #9 is connected to the receiving instrument, 24VDC
will be applied to the receiving instrument. This may cause
damage to that instrument.
Note: In both of the above cases 1 and 2, a short-term faulty
connection may not cause any problem. If the faulty
connection is kept for more than one hour, the problem
described will occur.
7. Terminal Connection
The following steps should be taken prior to the connection.
8. Power Line Connection
The terminals for power supply connection (
①
and
②
) are covered
with a plastic plate for safety (see Fig. 1).
Open the cover plate and connect the power lines to the terminals
(see Fig. 2).
Return the cover plate to its original position (see Fig. 3).
4
5
1
2
P/+
N/-
4
5
4
5
Terminal Block
Cover
Note: For your safety, do not make any electrical connections or
disconnections with power supplied to the instrument. Make
sure that all terminal screws are properly tightened each time
you finish the tightening.
9. Settings
You can use the rotary switch (GAIN) for rough and Span Trimmer
(S1) for fine adjustment of output signal. Input signal ranges from
0-10% to 0-100% can be proportionally adjusted to 0-100% of
output. For the procedure, refer to the following:
1. Set the GAIN switch so that the following formula is met:
80%
≤
Input span × GAIN
≤
120%
2. Refer to section 11 “Adjustment” and adjust the Span Trimmer
(S1) to get 100% output while monitoring the output.
Ex. 1) When an input range of 4 to 5.6mA is made to correspond to
0 to 100%:
Input span = (5.6 – 4)/16*100 = 10.0%
Set the GAIN switch to 8.45.
Input span 10.0% × 8.45 (GAIN) = 84.5%
Turn the Span Trimmer (S1) to adjust the output to 100%.
(1) Loosen the terminal screw.
(2) Insert the tip of a
screwdriver bit beneath
the washer and push it
up to make ample room
to receive a cable.
Fig. 1
Fig. 2
Fig. 3
