SOR 503FR Fixed Range Pressure Transmitter - Manual (Page 2)

2/4 Form 963 (03.13) ©SOR Inc.
Installation
Ensure that wiring conforms to all applicable local and national electrical codes and install
unit(s) according to relevant national and local safety codes.
Before installing the transmitter, verify that the range stated on the transmitter label is
suitable for the pressure to be measured.
The transmitters are designed to be self-supporting in any plane when rigidly mounted by
the pressure port (1/4” NPT process connection). Thread the transmitter in place using the
wrench flats provided.
Avoid mounting the transmitter near a heat source which is liable to overheat the
instrument or cause a temperature gradient across it. If this is unavoidable, introduce
a heat shield to deflect radiated heat and thus maintain the transmitter at a uniform
temperature within the specified limits.
Although the operating temperature of the transmitter extends to below 32 o F, fluids must
not be allowed to freeze in the pressure port. Failure will occur due to the expansion of the
frozen fluid in the contained volume of the pressure port causing gross over-pressurization.
A failure of this nature is not covered by warranty.
Wiring Details
The 503FR is designed for use in a 2-wire, 4-20 mA system. A system of this type
requires that the measuring instrument alter the current consumption of an electric circuit
in proportion to pressure changes. The changes in current may be measured using suitable
instruments. Due to the design of the transmitter, it is unable to produce currents less than
approximately 3.3 mA. Should the transmitter output be “locked” at a figure of this order,
it is indicative of a fault and the system should be checked immediately.
Schematic diagrams for incorporation of the transmitter into a control or display loop are
shown below. The supply voltage at the transmitter terminals must be between 10 and 32
Vdc on std. units, and between 10 and 28 Vdc on intrinsically safe units. Polarity of the
transmitter wiring is essential for proper operation.