Adtech RBX 272 Instruction Manual

1.0 INTRODUCTION
These instructions refer to the above models. Supplementary
sheets are attached if the unit has special options or features.
For detailed specifications, see page 4 or refer to the Data
Bulletin. All AD TECH instruments are factory calibrated and
supplied with a label detailing the calibration. Adjustments
are normally not necessary.
performed to verify calibration before installation to ensure
that it matches the field requirement.
2.0 GENERAL DESCRIPTION
The ADTECH Model RBX 272 and RBX 274 Two-Wire RTD
Transmitters provide high accuracy conversion of resist a nc e
bulb sensor input signals to a standard 4-20 ma de process
signal.
The RBX 272 provides 600 volts ac or 1000 volts de isolation
from the input to output/power supply, whereas the RBX 27 4
is non- isolated.
The primary features of the RBX 274 and RBX 272 are:
• Wide range-Covers the entire range of 100 ohm
Platinum or 120 ohm Nickel RTD's-jumper selectable.
• Provide linearization of Platinum and Nickel RTD's.
• Zero elevation or suppression up to 100% of the major
range with a 16 position switch.
• Field adjustable via plug in jumpers and potentio-
meters.
• High accuracy, repeatability, and ambient effect stability.
• RFI resistant.
• NO INTERACTION of ZERO and SPAN.
• Small size-DIN mounting package. Only 1 "w x 3.1 "h
x 3.6"d.
• Options for NEMA housings, SNAP TRACK and
surface mounting.
3.0 INSTALLATION
The instrument is supplied in a non-metallic general purpose
DIN rail mount 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. For detailed mounting
and installation refer to page 4 inside.
Electrical Connections
The wire used to connect the instrument to the control
system Input / Output should be twisted pair(s) and sized
according to normal practice. Shielded cable is not normally
necessary (if used, the shield must be grounded at terminal 1
of the ADTECH instrument and left floating at the sensor).
A six position compression terminal block is provided for the
1/0 and power connections. A housing ground terminal is not
required due to non-metallic housing.
RBX 272 Two-Wire ISOLATED Resistance Bulb Transmitter
RBX 274 Two-Wire NON-ISOLATED Resistance Bulb Transmitter
Instruction Manual
A simple check must be
-1-
Controls
Instrument co n trols consist of the following:
• Two 16 position rotary switches for COARSE ZERO
and COARSE SPAN control.
• One 4 position Jumper for RTD type.
• One 4 position jumper for selection of major range.
• One 2-position jumper for input ZERO control.
• Multiturn FINE ZERO and SPAN controls.
Multiturn controls are accessible from the front of the unit.
4.0 MAINTENANCE
These instruments are electronic and require no maintenance
except periodic cleaning and calibration.
If the unit appears to be mis-operating, field wiring and/or
associated circuits should be checked. MOST problems are
traced to these areas.
If the problem appears to be the instrument, it may be
checked as installed or removed
detailed in sections 6.0 and 7.0.
5.0 CONNECTIONS
Standard connections are shown below and on the instrument
face plate, Data Bulletin or on attached supplementary
sheets.
ADTECH
NOTE: See 2 Wire and 4 Wire RTD connection on page 2.
for a bench check as
-�
RBX
TWO WIRE
TRANSMTR
(3-97) 190-A-00007 4-B