www.delta
-
mobrey.com
IOM
-
SENTRY
-
Ex
-
C: MAY 2020
Installation, Operation &
Maintenance
Instructions
Sentry Series
Models P01, P02, P03 (Pressure Switches)
Models D01, D02, D03 (Differential Pressure
Switches)
Models T01, T02 (Temperature Switches)
General
The unit is manufactured, checked and supplied in
accordance with our published specification, and
when installed and used in normal or prescribed
applications, with the lid in place and within the
parameters set for mechanical and electrical
performance, will not cause danger or hazard to life
or limb.
THE USERS ATTENTION IS DRAWN TO
THE FACT THAT, WHEN THE UNIT IS
‘
LIVE
’
WITH RESPECT TO ELECTRICAL
OR PRESSURE SUPPLIES, A HAZARD
MAY EXIST IF THE UNIT IS OPENED OR
DISMANTLED.
UNITS MUST BE SELECTED AND
INSTALLED BY SUITABLY TRAINED AND
QUALIFIED
PERSONNEL
IN
ACCORDANCE
WITH
APPROPRIATE
CODES OF PRACTICE SO THAT THE
POSSIBILITY OF FAILURE RESULTING IN
INJURY OR DAMAGE CAUSED BY
MISUSE
OR
MISAPPLICATION
IS
AVOIDED.
Operating Principles
Pressure Switch models P0* and Differential
Pressure Switch models D0* are diaphragm
operated switches.
These diaphragms generate a force proportional to
the applied pressure and are balanced by a user
adjustable control spring. When the force exceeds
that created by the control spring, the diaphragm
moves causing a push rod to actuate a snap
-
acting
micros
-
witch.
Temperature models T01 & T02 work in the same
way as the Pressure models with the exception that
the applied pressure comes from the expansion of a
vapour enclosed in either a rigid stem or semi
-
rigid
thermal system.
CERTIFICATIONS
Flameproof models
carry the following label
markings:
This equipment may be used in zones 1 & 2 with
gases groups IIA, IIB & IIC and dusts groups IIIA,
IIIB & IIIC for temperatures classes T1, T2, T3, T4,
T5 & T6.
Intrinsic Safety Model
Input limitations for intrinsic safety:
Ui = 30V, Ii = 300mA, Pi = 0.6W
This equipment may be used in zones 0, 1 & 2 with
gases groups IIA, IIB & IIC and dusts groups IIIA,
IIIB & IIIC for temperatures classes T1, T2, T3, T4,
T5 & T6.
Special Conditions of Use
Intrinsically safe models
1.
The Sentry Pressure, Differential Pressure
and Temperature Switches must not be
installed in a location where moving dust flow
can generate an electrostatic charge on the
equipment.
2. The Sentry range of pressure switches may be
provided with an aluminium alloy or stainless steel
enclosure. For models that have an aluminium
enclosure, identified in the model number by
5xxxxxxxxxxxxxxxx where 'X' describes other
parameters of the equipment, the enclosure must be
installed in such a manner that it is protected from
sources of impact and friction when installed in its
end
-
use application.
INSTALLATION
Mounting (All models)
The instruments are designed to be mounted
vertically with the process connection underneath.
However, mounting up to 45° from the vertical in any
plane is acceptable, although a small calibration
shift may occur.
