Maintenance; Special Conditions For Safe Use - Delta Controls S24 Installation, Operation & Maintenance Instructions Manual

IF ADJUSTING THE SET-POINT, IT IS
IMPORTANT TO USE A CALIBRATED
PRESSURE SOURCE RATHER THAN
THE REFERENCE SCALE PLATE TO
ENSURE ACCURATE SETTING OF THE
SWITCH.
NOTIFIED
PED
EMPLOYED
WITNESS THE SETTING OF CAT IV PED
PRODUCTS.
Though the unit may be set anywhere within its
range, for optimum performance, it is good practice
to have a set point value between 25% and 75% of
span.
The striker screw and lock nut are factory set and
should not be adjusted. Should these parts be
accidentally loosened, please contact Delta for
assistance.

MAINTENANCE

Inspections should be carried out at quarterly to
yearly intervals depending
conditions. Isolate the unit from process and power
and remove the lid.
tightness. Check that cable tails are not fouled or
chafed. Check for internal condensation. Check
that the gasket is seated properly in the lid recess
and is not worn. Keep the enclosure and lid clear of
dust build up. It is recommended that instruments
used to provide an alarm are operated periodically
to ensure they are functioning correctly. If further
maintenance is required seek advice from DELTA
CONTROLS before
replacement of parts.

SPECIAL CONDITIONS FOR SAFE USE

Applicable to all flameproof models of Industrial
series (Pressure switch series S20).
1. The flamepath between the pushrod and the
bush assembly has a maximum diametrical
clearance of 0.12 mm, which is less than
that permitted by Table 2 of standard EN
60079-1. The
diametrical clearance is not exceeded in
service.
Additional special condition for safe use that
applies to model 2S24 and 3S24 only, when used
in the boundary between an area requiring EPL Ga
and an area requiring EPL Gb.
2. The partition wall (the process diaphragm) is
less than 1 mm thick and shall not be
subjected to environmental conditions that
adversely affect the partition wall.
WHERE NECESSARY
BODY SHOULD
TO CARRY OUT
upon operating
Check all terminals for
attempting repair
user shall ensure
www.delta-controls.com
3. The unit shall be tested in such a way that the
operational
pressure or temperature limits) stated on it by
the manufacturer are verified.
A
NOTE: Under normal operating conditions where
BE
the process is not continually cycling above and
OR
below the set point, the wear will be minimal. To
examine for wear remove the pressure sensor from
the bottom of the enclosure and examine the rod
and bush assembly for obvious wear. Do not attempt
to remove the assembly and if in doubt seek
assistance from Delta Controls.
DIMENSIONS
Models S21, S22, S24 (Pressure Switches)
or
this
IOM-INDUSTRIAL REV.C: MAY 2015
parameters (for example,