Differential Pressure Indicator0 pages

APPLICATION
The BOLL Differential Pressure Indi­
cator is a robust and compact device
indicating the contamination level of
the ­ ilter elements.
f
The differential pressure between fil­

BOLL Differential
Pressure Indicator
TYPE
TYPE
TYPE
TYPE

4.36.1
4.36.2
4.46.1
4.46.2

ter inlet and filter outlet is the meas­
urable indicator for the contamina­
tion degree of the filter element.
When the preset maximum value of
differential pressure is reached, the
filter needs to be cleaned.
The colour of the disc segments vis­
ible in the two displays indicates
the contamination degree: The red
segment rises proportionally to the
level of contamination. When the
segment is completely red, the dif­
ferential pressure limit is reached.

DESIGN AND OPERATION
Inside the device is a plunger which
is held in zero position by a spring.
As differential pressure rises with in­
creasing contamination, the plunger
is displaced against the resistance of
the spring. By magnetic transmission
the display disc turns according to the
movement of the plunger and shows
more and more red segments. The
setting of the requested differential
pressure is effected by factory instal­
lation of a corresponding spring.
Differential Pressure Indicators with

the contacts of the two reed-switches

In case of type 4.46 the internal parts

integral electronic contacts are pro­

are activated magnetically.

are made of stainless steel and for

vided with two switches which can

u
­ se at an operating pressure of up

be independently used either as

The housing of the Differential Pres­

to 160 bar. To avoid the danger of

switching contact or alarm contact.

sure Indicator is made of coated

electrostatic charge, the cover

At 75% and at 100% of the preset dif­

die-cast aluminium and for use at an

glass may only be cleaned with a

ferential pressure threshold value,

operating pressure of up to 100 bar.­

damp cloth.