4
IM-P-20200627-01
<1. Introduction>
1.
Introduction
The EJA56
5
E solid-state pressure and level
transmitters are based on a piezoresistive silicon
sensor, with a very high burst pressure. The
sensor element is mounted in a stainless steel
"foot". A temperature sensor is mounted inside the
foot to and is used for active temperature
compensation. A strong stainless steel “flush”
diaphragm protects the sensor from the process
medium. A minimal amount of special oil fills the
chamber surrounding the sensor and transfers
pressure from the flush mounted diaphragm to the
sensor hydraulically.
Pressure on the sensor element creates a small
deflection of the silicon substrate and bridge
network. The resulting strain in the silicon resistors
causes a change in the bridge resistance that is
proportional to the pressure being applied. The
transmitter electronics detect this change in the
bridge resistance and converts it into the measured
value. The amplifier system is based on a single
Integrated Circuit, which ensures perfect linearity in
the output, all within an accuracy of 0.1 %.
1.1 Description
The EJA565E transmitter is specially designed with
a flush mounted diaphragm so it fully meet the
needs of the food, pharmaceutical, chemical and
other industries. Standard wetted parts are made of
316L SST, other materials are also available, like
Hastelloy C. Various process connections can be
adapted and available for manufacture;
(1.5”, 2” and 3” tri-clamp), SMS (1.5” and 2”), dairy
milk couplings (DN 25, 40 and 50), flanges (DIN
and ANSI) and sanitary weld-on nipples (ø 48, 62
and 85 mm.), among others.
All transmitters are temperature compensated,
which means that var
ying
process temperatures
have nearly no effect on the accuracy of the output
signal.
1.2 Barometric Reference
The EJA56
5
E is a “relative transmitter” which
means that barometric changes will not affect the
zero. The venting is placed in the cover of the
electronics housing next to the cable entry and is
the filter for the barometric reference to atmospheric
pressure.
The vent mechanism must be kept clean.
Certain variants of the EJA56
5
E are designed to be
non-clogging and are capable of being cleaned
inside. Various process connection types are
manufactured according to 3
-
A (74-06)
requirements such as Tri-Clamp and others.
