www.delta-mobrey.com
IOM-SENTRY-Ex-C: MAY 2020
Use only certified adaptors for Zone 1/Div 1.
Unused entries are to be fitted with suitably certified
stopping plugs.
The three switch terminals are clearly marked
“NORMALLY CLOSED”, “NORMALLY OPEN” and
“COMMON”.
The following diagram can be used as a guide for
wiring.
Insert bare wires fully into the terminal block and
tighten securely. Keep wiring tails to a minimum and
check that wires do not interfere with the operating
mechanism. Use the earthing / grounding points
provided.
BEFORE CLOSING THE LID:
• ENSURE WIRE IS CLEAR OF ALL
MOVING PARTS.
• ENSURE THAT WIRES DO NOT
TOUCH THE LID AS IT IS CLOSED.
Close the lid, being careful not to trap any wires in
doing so. Securely tighten the M3 lid locking screw
set provided using a 1.5mm hex key.
OPERATION
Adjustments
Pressure and Temperature Switches are supplied
calibrated at the midpoint of their range and to a
falling pressure or temperature unless otherwise
specified.
To re-calibrate:
1. Isolate the instrument from the process and
power.
2. Slacken the set point lock screw.
3. Using a suitable spanner, rotate the range
adjuster clockwise to increase the set point and
counter-clockwise to decrease the set point.
4. Tighten the set point lock screw.
5. Close the instrument lid and tighten lid lock screw
They can be mounted either direct to process, or to
a wall or panel using the mounting holes provided.
Select the mounting point so as to avoid excessive
shock, vibration or temperature fluctuation.
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. Use a
spanner to support the process connection when
fitting the instrument.
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 (T01 - 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 (T02 - 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.
Wiring
DISCONNECT ALL SUPPLY CIRCUITS
BEFORE WIRING
WIRE IN ACCORDANCE WITH LOCAL
AND NATIONAL CODES. USE CABLES
NO LARGER THAN 2.5 MM2 (14 AWG)
DO NOT EXCEED ELECTRICAL RATINGS
STATED IN LITERATURE AND ON
NAMEPLATES.
1 or 2 electrical entries are provided, into which
cable glands can be assembled. The thread type
and size is marked on the enclosure, just below the
connection. Select a suitable cable gland which will
maintain the IP rating of the instrument.
USE ONLY SUITABLY ZONE 1 CERTI-
FIED CABLE GLANDS OR STOPPING
PLUGS. CABLE TEMPERATURES MAY
EXCEED 80°C. USE ONLY CABLES WITH
SUITABLE OPERATING TEMPERATURE
RANGE.
