www.delta-controls.com
IOM-GR-A : AUGUST 2016
Flameproof Models
Flameproof models carry the following label
markings:
This equipment may be used in zones 1 & 2 with
flammable gases and vapours with apparatus groups
IIA, IIB & IIC for temperatures 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 PERMANENTLY ATTACHED LEADS
MUST
BE
SUITABLY
PROTECTED
AGAINTS MECHANICAL DAMAGE AND
TERMINATED IN A SUITABLE JUNCTION
OR TERMINAL FACILITY.
Models with Junction Boxes
Junction boxes with Exe approval carry the following
label markings:
This equipment is only certified for use in ambient
temperatures in the range –20°C to +40°C for T6
and should not be used outside this range.
Option include:
Code ‘C’: see Fig 1
Code ‘D’: same dimensions as code ‘C’ but Exe
approved for use in Zone 1.
Code ‘V’ and ‘W’ same dimensions as code ‘C’
but Exia approved for use in Zone 0.
Code ‘J’ :see Fig 2. Exe approved for use in Zone
1.
Note
: When weatherproof junction box code ‘C’
is fitted the unit must not be used in hazardous
areas unless the circuit or system to which it is
connected is Intrinsically Safe.
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. They can be mounted either direct to
process, or to a wall or panel using the back plate
provided. Select the mounting point so as to avoid
stresses, excessive shock, vibration or temperature
fluctuation being imparted to the switch during
operation. Instruments should be mounted to avoid
excessive heat transfer from the process lines or
adjacent plant. To avoid undue stresses being
imparted to the instrument when wall/panel
mounted, it is recommended that a short length of
flexible line be installed between the instrument and
process line. If sudden changes of pressure
(pulsations) are likely then we recommend that
snubbers are fitted between the process line and
instrument.
ALWAYS HOLD A WRENCH ON THE
PRESSURE ENTRY HEX WHEN MAKING
PRESSURE CONNECTION TO THE
SWITCH. DO NO TIGHTEN BY TURNING
THE ENCLOSURE.
CHECK THE CONNECTION THREAD SIZE
AND SPECIFICATION ON THE UNIT TO
AVOID
MIS-MATCHING
WITH
THE
PROCESS CONNECTION ADAPTOR. SEE
DIGIT 11 OF PRODUCT CODE.
Mounting (Model GR7- Rigid Stem)
Assemble the unit via a thermowell, using the
spanner facility provided and ensuring that:
a) the sensing bulb is fully immersed in the process
temperature
b) the sensing bulb does not bottom out in the
thermowell which could cause damage
Mounting (Model GR7 - Capillary system)
Mount the sensing bulb so that the capillary end is
above the bulb and the bulb is level with, or no more
than 250mm below the base of the instrument. The
stem is fitted with a sliding compression gland to
accommodate different thermowells.
ATEX
