SCT 302
Isolated Convertor-DC Powered
Instruction Manual
1.0 INTRODUCTION
These instructions refer to the above model. Supplementary
sheets are attached if the unit has special options orfeatures.
For detailed specifications, see page 4 or refer to the Data
Bulletin. All ADTE CH instruments are factory calibrated and
supplied with a label detailing the calibration. Adjustments
are normally not necessary. A simple check should be
performed to verify calibration before installation to ensure
that it matches the field requirement.
2.0 GENERAL DESCRIPTION
The ADTE CH SCT 302 is an Isolated Signal Transmitter that
accepts process input signals such as 4-20 ma de and
converts them into a standard control signal output such as
4-20 ma de, 1-5 vdc or 0-1 O vdc.
The input is electrically isolated from the output and the
power supply by 600 volts ac or 1000 vdc peak.The SCT 302
is powered by 15-42 vdc. The negative rail of the output is
common with the negative rail of the de power supply.
The output is a true current source and provides process
signals such as 4-20 mA, 0-20 mA DC, 0-1 mA, 0-10 mA, or
alternatively, a voltage signal of 5 VDC full scale. Other
current and voltagle Inputs/Outputs (1/0)
are available as
spectified on the Data Bulletin and on page 4 inside.
3.0 INSTALLATION
The instrument is supplied in a DIN rail mount general
purpose enclosure as standard. NEMA 4 and 7 enclosures
are optionally available. Installation area/location must agree
with the supplied instruments including operating temperature
and ambient conditions.
Electrical Connections
The wire used to connect the instrument to the control
system 1/0 should be a twisted pair(s) and sized according
to normal practice. Shielded cable is not normally necessary
(if used, the shield must be grounded at the input negative
of the ADTECH instrument and left floating at the sensor).
Six position compression terminal blocks are provided for
1/0 and power connection. A housing ground terminal is not
required due to non-metallic housing.
Controls
Multiturn ZERO and SPAN controls are provided to calibrate
the instrument. The multiturn controls are accessible through
the instrument front panel and are clearly marked for ease
of use. Other internal range selection jumpers are provided
for ease of field rangeability as listed below.
one 16-position coarse ZERO SWITCH (SWI)
one 16-position coarse SPAN SWITCH (SW2)
4.0 MAINTENANCE
These instruments are electronic and require no maintenance
except periodic cleaning and calibration verification. If the
unit appears to be mis-operating it should be checked as
installed per section 6.0 or removed for a bench check per
sections 6.0-7.0. MOST problems are traced to field wiring
and/or associated circuits. If the problem appears to be with
the instrument, proceed to sections 7.0.
5.0 CONNECTIONS
Standard connections are shown below and on the instrument
face plate, Data Bulletin or on attached supplementary
sheets.
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ADTECH
SCT302
COM.
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( 4-98) 190-A-000076· 8-