Ionisation Current Measurement - baltur TBML80 PN Manual De Instrucciones

stop the burner immediately after the two meter readings.
13) To vary the maximum supply of gas output, use the airflow
regulator because the gas output automatically adjusts to
the air supply. It is therefore necessary to use the cam which
adjusts the maximum opening position of the air shutter (see
adjustment instructions 0002933650). The opening angle of
the air shutter has to be reduced to reduce the gas supply and
vice versa. To vary the air/gas ratio see the instructions for the
pneumatic gas valve installed.
14) Subsequently check combustion with the special instruments.
For a correct air/gas ratio you must find a carbon dioxide (CO
value for the methane that is at least 8 % or O
burner supply up to an optimal value of 10 % or O
maximum supply. It is essential to check, with a suitable instru-
ment, that the percentage of carbon monoxide (CO) present in
the fumes does not exceed the limit set by regulations at the
time of installation.
15) After setting operation to the maximum thermal output, it is
necessary to set the airflow servomotor at the minimum posi-
tion, turning the modulation switch to the MIN position. With the
burner operating at minimum power, in the event it is necessary
to vary the combustion conditions, follow the adjustment instruc-
tions for the pneumatic gas valve installed. It is very important
to carry out an instrument assisted check on combustion and
modify, where necessary, the initial visual setting, this must
also be effected in a series of intermediate positions of the
modulation range set for the air damper.
16) Now check the proper automatic operation of modulation.
17) The air pressure switch makes the equipment safe (block) if
the air pressure is not at the expected value. The pressure switch
must therefore be set to close the contact (closed during opera-
tion) when air pressure in the burner is sufficient. Please note that
if the contact meant to be closed during operation does not close
(insufficient air pressure), the equipment carries out its cycle but
the ignition transformer is not switched on and the fuel valves
do not open. As a result, the burner stops in a blocked state.
To verify that the air pressure switch is operating correctly, while
the burner is ignited on first flame only, increase the adjustment
value until the switch triggers an instant "blocked" stoppage
of the burner. Release the burner by pushing the appropriate
button and readjust the pressure switch until preventilation air
pressure can be detected. The pressure switch connection
circuit is self controlling. Therefore, the contact which is meant
to be closed in a non operating state (fan stopped and thus no
air pressure in burner), should in fact be in this state, otherwise
the command/control equipment will not be switched on (burner
remains inoperative).
18) The pressure switches for checking gas pressure
(minimum and maximum) prevent the burner from operat-
ing when the gas pressure is not within the required min/max
value range. The specific function of the pressure switches
clearly reveals that the pressure switch for controlling mini-
mum pressure must use the contact which is closed when
the pressure switch detects a pressure value above the value
it is set to, while the pressure switch for controlling maximum
pressure must use the contact that is closed when the pres-
sure switch detects lower pressure than the value it is set to.
Minimum and maximum gas pressure switches must be set when
the burner is tested. Setting depends on pressure detected from
time to time. The pressure switches are connected electrically in
sets, therefore tripping any of the gas pressure switches (in the
sense of opening the circuit) will prevent the equipment and thus
the burner from working. When the burner is working (flame on),
tripping the gas pressure switches (opening the circuit) will shut
down the burner immediately. When testing the burner, it is very
important to check that the pressure switches are working prop-
erly. By using the adjustment devices, it can be verified whether
)
the pressure switch that stops the burner actually operates (i.e.
2
=6% at minimum
opens the circuit).
2
= 3% for
2
19) Check the action of the flame detector (see chapter CON-
TROLS).
20) Check the proper function of the boiler thermostats or pressure
switches (when triggered they must stop the burner).
Check that ignition is correct because if the mixer is
!
shifted forward, the outgoing air speed may be too high
to permit ignition. In such a case, it is necessary to move
the mixer backwards degree by degree until reaching
the position in which the ignition is regular and accept
this new position as definitive.
We remind you that is preferable, in the case of the small flame,
to limit the quantity of air to the least possible needed for safe
ignition, even in the most difficult circumstances.

IONISATION CURRENT MEASUREMENT

To measure the ionisation current, remove the jumper between
terminals 30-31 on the printed circuit with the burner off (see
diagram). Connect a microammeter to the terminals (with a
suitable scale to have the burner restart). Once the flame has
appeared it will be possible to measure the ionisation current, the
value of which must be higher than 3 µA to ensure the working of
the equipment . After making the measurement, reset the jumper
that has been disconnected.
19 / 28
0006081470_201105
E
N
G
L
I
S
H