SK300-XL Steam Humidifier
26
Control PC Board
Main Printed circuit board designated is common to all SK300-XL series humidifier, ON/OFF or modulating; this
pc board is equipped with an advanced microprocessor which controls all the humidifier functions.
The Printed circuit board which is directly connected onto the main pc board is installed only on modulating
model (suffix M).
Staging PC Board (HEC002SK) is controlling the 2 on/off stages (Contactor 2 and Contator3)
Main p.c. board
There are 3 water level L.E.D.’s in the upper right hand
side. They indicate the relative water height as sensed
by the water level sensor.
o
If HI is illuminated: water supply valve shuts off,
o
If LO is
off
: An evaporation chamber filling is ordered,
water supply valve opens
.
o
If
LA
is
off
: No water is detected by the water level
sensor, the power to the elements is shot off.
The 3 status L.E.D.’s at the center left side operate as
follows:
o
FILL indicates that the water supply valve is feeding
water.
o
DRAIN indicates the drain valve empties the
container.
o
CONT indicates that power is supplied to the
elements and the humidifier is producing steam.
TEST button should be used when commissioning the
humidifier; this will initiate a pre-programmed start-up
cycle. The start up cycle cleans the supply water and
the evaporation chamber (see section 1
1
– start-up).
This button enable also the set point control of the
humidistat to humidifier display (see section
9
.2 –
Programming) (this is available only on Modulating
model).
RESET button enable the bypass of start up sequence.
(Illus. 53)
Modulating p.c. board
The 3 jumpers at the center of the p.c. board (Control Input) are used for proper selection of the incoming
control signal. See section Control signal set-up
The 3 jumpers at the bottom of the p.c. board (Humidity Input) are used for proper selection of the
incoming humidity signal. See section Humidity signal set up.
Staging p.c. board
This PCB does not require any set-up, it is connected to the contactor 2 and contactor 3 controlling the 2 on/off
stages.
PCB
970
81
9
RE
V
. C
TOP PCB
MODULATING
CONTROL
INPUT
HUMIDITY
INPUT
4-20mA
0-10V
2-10V
4-20mA
2-10V
0-10V
