MAGUIRE MPL Series, Installation Operation & Maintenance, Page: 16 / 23

M A G U I R E P R O D U C T S , I N C .
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M P L M L S e r i e s V e n t u r i L o a d e r s
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OPERATION
When material level in the hopper drops enough to uncover the sensor, the air solenoid is turned
on. High pressure air passing through the vacuum generator creates a high volume, low
pressure, flow of air into the hopper. This flow of air pulls material from the source and conveys it
into the hopper.
A steel plate in the hopper serves to deflect the blast of pellets and slow their speed. This
prevents high speed bouncing of pellets in the hopper, keeping them from escaping under the
edges of the hopper lid. The Air stream is expected to escape from the hopper by passing under
the edge of the lid. The lid must not be gasketed.
When the sensor is covered, loading stops. It is not unusual for load times to be short. While you
may be accustomed to seeing other loaders go through lengthy load time cycles, if this loader
cycles on for only a few seconds, it is an indication that the unit is loading quite well.
ALARM models
If the letter "A" is part of the model designation on MPL-A (not the ML-A), then you have a control
box with an ALARM function. In this case a timer is running whenever the venturi is loading. If
loading continues for two minutes, the timer will turn on the strobe light and beeper alarms
automatically.
On model MPL-AS only, if five more minutes pass without the sensor being covered, a third
device is turned on. This signal will drive a shut down circuit, either a relay that is wired to stop
your process, or an air operated flow control gate, that stops the flow of pellets to the process.
At any time, if the sensor is covered for even a moment, the alarms reset and timers are reset to
zero.
Timers are preset for 2 minutes and 5 minutes, respectively. These times can be changed by
moving jumpers on the board. Note: The ML-A does not have a timer adjustment. On the ML-A .
the alarm is set for 2 minutes, meaning that if a sensor is not re-covered within 2 minutes the
controller will alarm.