Antunes, AJ MS-150/155 - Manual (Page 18)

MIRACLE STEAMER
18 P/N 1010699 Rev. M 12/06
MAINTENANCE (continued)
Technical Theory of Operation
When the Rocker Switch (power On/Off) is ON, line
voltage flows to the primary side of the step down
transformer. The transformer’s secondary side supplies
12 and 24 VAC to the Control Board.
Once powered, and provided that the Generator tem-
perature is below 380° F (193° C), the Control Board
calls for heat by supplying 10 - 15 VDC to the Solid
State Relay terminals 3(+) 4(-). Once powered, the
Solid State Relay closes terminals 1 and 2 which allows
line voltage to flow to the Generator.
As the Generator begins to heat up, a type “K” thermo-
couple monitors the internal Generator temperature. As
the heat continues to increase, so does the thermocou-
ple’s DC millivolts. Once the Generator’s temperature
rises to 380-420° F (193 - 215° C), the thermocouple is
generating approximately 7.5 - 9.0 DC millivolts.
The Control Board receives these millivolts and pro-
ceeds to remove the 10 - 15 VDC to the Solid State
Relay since the heating circuit has now become sat-
isfied. Then, relay terminals 1 and 2 open, and the
Generator stops heating.
When the Operate, Single Shot, or Start/Stop button
is pressed, the Control Board is signaled to supply 24
VAC to the solenoid valve used in models MS-250/255
or the water pump used in models MS-150/155/355 for
a split second.
The solenoid valve opens, or the water pump runs, and
allows a shot of water (approximately 25ml or 3-4 table-
spoons) to flow onto the generator surface for steam-
ing.
NOTE: If the display is in a Timed Cycle (counting
down), the Control Board will continue to activate
the solenoid valve or water pump for repeated
shots of water, once every 20 seconds, and for
the duration of the cycle time displayed. See the
Programming section of this manual for more infor-
mation.
Since the Generator Cover is secured in place with
a wing nut, the steam is forced downward through
the Generator Steam Ports and onto the product.
The Control Board’s parameters can be custom pro-
grammed for the over all cycle steam time (CYC), as
well as the interval time in seconds (SHO) when each
shot of water occurs, and also the water volume (H2O)
used per each shot of water. This Control Board also
incorporates several Status Indicator LEDs. See the
Operating and Programing sections of this manual).
An audio signal will sound for 3 seconds at the end of
a Time Cycle. If the heating circuit continues to call for
heat and the Generator overheats, a manual, resettable
Hi-Limit Thermostat will trip and open the generator
circuit.