Finterm Joannes G 50/2 Manual De Instrucciones De Manejo Y Mantenimiento página 52

ADJUSTING MULTIBLOC VALVE
MB-VEF
Adjusting field
CONCEPTS AND DEFINITIONS
Max working pressure p
Max working pressure to carry out all the func-
tions safety.
Pressure field during inlet p
Pressure field between the minimum and maxi-
mum pressure during inlet, securing a very
good adjustment.
Pressure of the blower p
Over-pressure generated by the blower of the
gas device. The static pressure of the combu-
stion air is representative for the mass flow. It
is the reference quantity for the pressure to the
burner pBr.
Pressure to the burner p
Pressure of the combustible gas before the
mixing device of the gas unit. Pressure after
the last control member of the gas safety and
control section. The pressure to the burner p
follows the pressure of the blower p
stment measure.
Pressure of the mean field p
Pressure during outlet of the pressure control
member before valve 2.
Combustion chamber pressure p
Pressure in the combustion chamber of the
heat generator.
The pressure o the burner chamber (over-pres-
sure or depression) may vary with reference to:
• power
• soiling
• section variation
max.
e
, AIR
L
, GAS
Br
Br
as adju-
L
a
.
F
15
• atmospheric conditions etc.
The pressure of the combustion chamber
opposes to the combustion air flow. Therefore
it has to be controlled as an influent. It is possi-
ble to disregard this influent by a proportional
adjustment V-1:1, as the pressure in the com-
bustion chamber has an equivalent effect on
both the mass flows of the combustion air and
of the combustible gas.
V ratio
Adjustable ratio between the pressure to the
burner p and the pressure to the blower p
Br
The differential pressures are effective for the
system of the collating membranes.
Δp
= (p - p ) and
Br Br F
Δp
= (p - p )
L L F
Correction of zero point N
Correction of the weight difference in case of
different length of the levers between the colla-
ting membranes for the air and the gas (V 1:1).
Possibility of variation of the original proportio-
nal control, parallel shifting (Offset).
Effective differential pressure p
The pressure drop with reference to the pres-
sure of the combustion chamber is determinant
for both the mass flows of the combustible gas
and of the combustion air.
.
L
, p
Br L