baltur GI 1000 Serie Mode D'emploi page 58

DESCRIPTION OF HOW THE VALVE OPERATES
Single-stage valves
When the valve receives the signal to open, the pump cuts in and the magnetic valve closes. The pump transfers
the oil from under the piston to above it, forcing the piston downward, which compresses the closure return spring
with the rod and plate. The valve remains in the open position while the pump and magnetic valve remain
powered. When the unit receives the signal to close (or if power supply is cut off) the pump shuts down, the
magnetic valve opens decompressing the chamber above the piston. The plate is closed both by the return
spring and by gas pressure. The flow rate for this valve is calculated to ensure full closure in less than one
second.
DESCRIPTION OF GAS PRESSURE SWITCH WORKING
The minimum and maximum gas pressure control switches have the aim of
preventing the burner from working when the gas pressure goes outside the
pre-set limits. The specific working of the pressure switches naturally means
that the minimum pressure control switch uses the NO contact (normally open)
to closed when the pressure switch detects a pressure greater than that set.
Similarly the maximum pressure switch acts on the NC contact (normally
closed) so that it is closed when the pressure switch detects a pressure below
that set. The adjustment of the minimum and maximum gas pressure switches
must therefore take place when the burner is being tested, according to the
pressure found from time to time. The pressure switches are electrically con-
nected in series, so the intervention (i.e. circuit opening) of any of the pres-
sure switches when the burner is working (flame on) causes the burner to shut
down immediately. Adjustment before switching on the burner: adjust the mini-
mum pressure switch at the scale's minimum and adjust the maximum pres-
sure switch at the scale's maximum. Adjustment after burner calibration: With
the burner at its maximum output, adjust the minimum pressure switch by
increasing the calibration until the burner switches off, read the calibration
setting on the adjustment ring nut and set this to 5 mbar less . With the burner
off, adjust the maximum pressure switch by reducing the calibration until the
NC contact (normally closed) opens. Read the on the adjustment ring nut and
adjust this by increasing it by 5 mbar.
Note: the pressure switch will be for minimum pressure if there is only one of these mounted on the gas train.
INSTRUCTIONS FOR THE ADJUSTMENT OF
LANDIS & GYR GAS VALVE MODEL
SKP 10.110 B27 - SKP10.111B27 AD UNO STADIO
This type of valve cannot regulate the gas flow
rate (closure/opening).
Screw "D" on terminal "IV" sets the "clean
contact" position which can be used for an
outside signal.
A = Driver identification plate
B = Flow direction indicator
C = Valve body identification plate
58
N° 8880
Rev. 06/11/90