baltur COMIST 180 Manual Installation, Use, Maintenance page 59

INSTRUCTIONS FOR SETTING LANDIS & GYR
mod. SKP 10.123A27 TWO STAGE GAS VALVES
DESCRIPTION OF HOW THE VALVE OPERATES
Servomotor
The hydraulic control system consists of a cylinder filled with oil and an
oscillating pump with thrust piston. There is also a solenoid valve located
between the intake chamber and the pump thrust chamber which serves to
close the valve. The piston moves against a sealed joint inserted into the
cylinder; in turn, this joint hydraulically separates the intake chamber from the
delivery chamber. The piston transmits the stroke directly to the valve.
A disk is secured to the valve shaft and can be seen through a slit in the
valve, indicating the stroke. Through an oscillating system this disk simul-
taneously activates the limit switch contacts for the partial and nominal
output positions.
Two - stage operation
When the valve receives the signal to open, the pump cuts in and the
magnetic valve closes. The pump transfers the oil under the piston to
above it, forcing the piston downward, which compresses the closure
return spring with the rod and plate. When the valve reaches the first
stage, a disk connected to the shaft activates contact "V1" by means of an
oscillating system. As a result, the pump cuts out and the valve remains
in the first-stage position.
The pump begins functioning again only when terminal 3 is powered either
from the control panel or directly by the power regulator. The full load stroke
terminates when the contact is tripped and the pump cuts out.
If the power regulator cuts off power supply to terminal 3, the magnetic
valve opens and the valve will remain open until the piston reaches the 1
stage position. If regulation is shut down because the power supply has
been cut off, terminals 1 and 3 are no longer powered - this causes the
servocontrol to close the valve in less than 1 second.
A = Driver identification plate
B = Flow direction indicator
C = Valve body identification plate
Remove cover "A" to access the gas regulation screws.
To set gas flow to the 1
screwdriver.
To set gas flow to the 2
screwdriver.
In both cases, tightening the screw increases gas flow, unscrewing it
decreases the flow.
Screw "D" in terminal "IV" regulates the position at which the "clean" contact
is activated. This can be used for an outside signal.
SUGGESTIONS FOR SETTING
1) We therefore advise you to prepare the burner for ignition by setting screw V1
(regulating the gas flow to the 1
control lever and the microswitch push-button does not exceed 1 mm (see
the figure below). Set the combustion air gate in a highly closed
position.
2) Second flame. Set V2 in the position where the gas flow required for
the 2 flame is obtained. Obviously, the position at which V2 is set (the
nd
distance between the microswitch control lever and the microswitch
push-button) must be greater than that set for V1.
st
Microswitch push-button for valve 1
Screw setting the opening for the valve 1
21 / 34
0006080095_200902
Rev. 06/11/90
flame, turn the screw in terminal I (V1) with a
st
flame, turn the screw in terminal III (V2) with a
nd
flame) so that the distance between the
st
Microswitch control lever for valve 1
N° 8881
Rev. 06/11/90
N° 8881
E
N
G
L
I
S
H
stage
st
stage
st
stage (V1)
st