www.delta-controls.com
IOM-GR-A : AUGUST 2016
Installation, Operation &
Maintenance
Instructions
GR Series
Models GR2, GR4 (Pressure Switches)
Models GR3, GR6 (Differential Pressure Switches)
Model GR7 (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.
THE MICROSWITCH ASSEMBLY WITH
FACTORY SEALED LEADS HAS BEEN
CAREFULLY
POSITIONED
AT
THE
FACTORY. ANY DISTURBANCE MAY
RENDER THIS UNIT INOPERATIVE.
Operating principles
Pressure Switch models GR2, GR4 and Differential
Pressure Switch models GR3, GR6 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 model GR7 works 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
Intrinsically Safe Models
Intrinsically safe models carry the following label
markings:
This equipment may be used in zones 0, 1 & 2 with
flammable gases and vapours with apparatus
groups IIA, IIB & IIC and with temperature classes
T1, T2, T3, T4, T5 & T6.
This equipment is only certified for use in ambient
temperatures in the range –40°C to +60°C for T6
and –40°C to +85°C for T4 and should not be used
outside this range.
The certificate number has an ‘X’ suffix which
indicates that special conditions of installation and
use apply. Those installing or inspecting this
equipment must have access to the contents of the
certificate or these instructions. The conditions listed
in the certificate are reproduced below:
THE APPARATUS MUST BE INSTALLED
SUCH THAT THE RISK OF IMPACT OR
ABRASION IS NEGLIGIBLE.
THE PERMANENTLY ATTACHED LEADS
MUST
BE
SUITABLY
PROTECTED
AGAINTS MECHANICAL DAMAGE AND
TERMINATED IN A SUITABLE JUNCTION
OR
TERMINAL
FACILITY WITH
A
MINIMUM DEGREE OF PROTECTION OF
AT LEAST IP6X.
THE INSTALLATION OF EXTERNAL
CONNECTIONS TO MODELS OF THE
APPARATUS
WITH
TERMINAL
ENCLOSURES MUST BE CARRIED OUT
USING APPROPRIATE CONDUIT OR
CABLE GLAND WITH A DEGREE OF
PROTECTION OF AT LEAST IP6X,
COMPONENT CERTIFIED BY AN EU
APPROVED CERTIFICATION BODY.
ATEX
ATEX
ATEX
