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TERMINAL CONNECTIONS
Connect the unit as in the diagram below.
■
EXTERNAL DIMENSIONS unit: mm [inch]
I/O PINS
17.5 [.69]
48 [1.89]
75 [2.95]
83 [3.27]
■
CONNECTION DIAGRAM
2
1
4
9
11
10
6
8
7
B
A
C
Installation Base
INPUT
2-WIRE XMTR
PWR SUPPLY
+
–
+
–
+
–
+
LOAD HHC
POWER
*
1
*
1. Hand-held communicator
2-WIRE
XMTR
B
A
C
250Ω
+
–
+
-
+
HHC
*
1
■
When used as current loop supply
B
A
C
250Ω
+
–
+
HHC
*
1
■
When used as isolator
INPUT
OUTPUT 1
5
3
CHECKING
1) Terminal wiring: Check that all cables are correctly con-
nected according to the connection diagram.
2) Power input: Check the power input voltage.
3) Input: Check that the input signal is within 0 – 100% of
the full-scale.
4) Output: Check that the load resistance meets the de-
scribed specifications.
250Ω±10% is required to use HART communication.
ADJUSTMENT PROCEDURE
This unit is calibrated at the factory to meet the ordered
specifications, therefore you usually do not need any cali-
bration.
For matching the signal to a receiving instrument or in case
of regular calibration, adjust the output as explained in the
following.
■
HOW TO CALIBRATE THE OUTPUT SIGNAL
Use a signal source and measuring instruments of sufficient
accuracy level. Turn the power supply on and warm up for
more than 10 minutes.
1) ZERO: Apply 0% input and adjust output to 0%.
2) SPAN: Apply 100% input and adjust output to 100%.
3) Check ZERO adjustment again with 0% input.
4) When ZERO value is changed, repeat the above proce-
dure 1) – 3).
MAINTENANCE
Regular calibration procedure is explained below:
■
CALIBRATION
Warm up the unit for at least 10 minutes. Apply 0%, 25%,
50%, 75% and 100% input signal. Check that the output
signal for the respective input signal remains within accu-
racy described in the data sheet. When the output is out of
tolerance, recalibrate the unit according to the “ADJUST-
MENT PROCEDURE” explained earlier.
LIGHTNING SURGE PROTECTION
M-System offers a series of lightning surge protector for
protection against induced lightning surges. Please contact
M-System to choose appropriate models.
M8DYH
5-2-55, Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
Phone: +81(6)6659-8201 Fax: +81(6)6659-8510 E-mail: [email protected]
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