temperature is reached. If indicator actuates after
resetting, replace element. If brass visual indicator
is fitted and actuates during ‘cold start’ (flag inside
indicator changes to red), it will automatically reset when
normal operating temperature is reached. If indicator
is still actuated after normal operating temperature is
reached, replace element.
NOTE: Option ‘P’ visual indicator has thermal lockout and manual
reset. No signal below 0°C (32°F), signal above 29°C (80°F).
6.3 If the electrical switch actuates (e.g. red light comes on)
during cold start, continue operating until the signal (red
light) goes out as system warms to normal operating
temperature. This feature can be used as ‘warm up’
indication in operating procedures. If the warning signal
(red light) remains or appears when system is warm,
replace the filter element.
6.4 Use of both positive indication (green light) and negative
indication (red light for dirty element) is recommended to
effectively monitor filter element life.
Electrical connections and ratings are dependent on
indicator chosen. Typical values only are shown below:
110 VAC
=
4A (inductive),
4A (resistive)
220 VAC
=
4A (inductive),
4A (resistive)
28 VDC
=
3A (inductive),
5A (resistive)
48 VDC
=
1A (inductive),
1.5A (resistive)
125 VDC
=
0.25A (inductive),
0.5A (resistive)
Maximum inrush - 24 amps.
Underwriter’s lab. Inc. listed ratings of pressure switch
(Microswitch) options are:
4 amps at 250 VAC
0.25 amp resistive at 220 VDC
0.50 amp resistive at 110 VDC
Electrical differential pressure switch operation:
When preset differential pressure is exceeded continuity
switches from Normally Closed (NC) - Common to Normally
Open (NO) - Common.
When differential pressure decreases below pre-set value,
continuity returns to Normally Open (NO) - Common to
Normally Closed (NC) - Common.
See individual indicator options for connection details.
UH310
UH310 Series
H I G H P R E S S U R E F I L T E R S
s e r v i c e
i n s t r u c t i o n s
3
Note: Painting of the filter housing is optional. The coating
on the filter housing is a suitable painting base. Cover the
differential pressure warning device and nameplate if painting
of the housing takes place.
4.8 Bleed the filter
4.8.1 UH310 series (cover service): Bleed the filter by opening
the vent plug (7) at the top of filter one and one half
turns. Jog system and fill filter until all air bleeds through
the plug, then torque tighten the vent plug to
12 ft/lb or 16Nm.
4.8.2 UH310H series (head service): Bleed the filter by opening
the blanking plug (6b) one and one-half turns. Jog system
and fill filter until all air bleeds through the plug, then
torque tighten the blanking plug to 40 ft/lb or 54 Nm.
Pressurize system fully and check for leaks; if leaks occur
refer to section 5.
5
Routine maintenance
5.1
Pall filters do not normally require special attention
except for periodic monitoring of the differential pressure
warning device. Schedule replacement of filter element
every six months or sooner, and have ample supply of
spare elements available.
5.2 If external leakage is noted, replace O-ring at leak. If
leakage persists, check sealing surfaces for scratches or
cracks; replace any defective parts.
5.3 Differential pressure devices actuate when the element
needs changing or because of high fluid viscosity in
‘cold start’ conditions. If ‘cold start’ conditions exist, see
Section 6.2 and 6.3.
5.4 A dirty system can quickly plug a new filter element,
especially with
Pall high efficiency filter media. It may
require one or two initial element changes to stabilize
element life. If element life is short or differential
pressure is excessive, filter may be undersized; refer to
the sizing and selection section of the product literature
or contact your local Pall representative.
5.5 Make sure element change labels are clean and
undamaged. Replace illegible labels with the appropriate
new labels.
6
Differential pressure devices
Reference should be made to product literature for dimensions,
operating parameters, part numbering, ordering information
and specifications.
6.1 Differential pressure devices actuate when the element
needs changing or because of high fluid viscosity in
‘cold start’ conditions.
6.2 If stainless steel visual indicator is fitted and actuates
during ‘cold start’ (red button extends 5mm, 3/16”), reset
by depressing the button when the normal operating
ENGLISH
WARNING:
USE FITTINGS OR ADAPTORS COMPATIBLE WITH
PORTS SUPPLIED AS SHOWN BY PART NUMBER
ON NAMEPLATE AND NOTED IN DATA SHEETS:
USE OF INCORRECT FITTINGS OR ADAPTORS CAN
CAUSE FILTER HOUSING OR MANIFOLD FAILURE
RESULTING IN LOSS OF PRESSURE AND POSSIBLE
SYSTEM FAILURE OR PERSONAL INJURY.
CAUTION:
Failure to bleed the filter housing adequately will
increase the dissolved air content of the system fluid
which will shorten fluid life and may cause other
problems in the system.
Figure 1a
- Stainless Steel Switch Circuit Diagram
COMMON
NORMALLY
CLOSED
(NC)
NORMALLY
OPEN (NO)
LOW DIFFERENTIAL PRESSURE
HIGH DIFFERENTIAL PRESSURE
Figure 1b -
Brass Switch Circuit Diagram
COMMON
Pin 1
NORMALLY
CLOSED
(NC) Pin 2
NORMALLY
OPEN (NO)
Pin 3
LOW DIFFERENTIAL PRESSURE
HIGH DIFFERENTIAL PRESSURE
