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1. DO NOT attempt to operate the PLASMA-PREEN unit with the door open since open-door
operation can result in harmful exposure to microwave energy. It is very important not to
defeat or tamper with the safety interlocks.
2. DO NOT place any object between the unit front face and the door or allow soil, cleaner or
residue to accumulate on sealing surfaces.
3. DO NOT operate the unit if it is damaged. It is particularly important that the oven door
close properly and that there is no damage to the: (1)door (bent), (2)hinges and latches
(broken or loosened), (3)door seals and sealing surfaces (4) the fittings in the rear of the
unit (removed or loose).
4. The unit should not be adjusted or repaired by anyone except properly qualified service
personnel.
VIII. GROUNDING INSTRUCTIONS
1. The PLASMA-PREEN system must be grounded and connected to the same ground as the
vacuum pump. In the event of an electrical short circuit, grounding reduces the risk of
electrical shock by providing an escape wire for the electric current. This unit is equipped
with a chord having a grounding wire with a grounding plug. The plug must be plugged
into an outlet that is properly installed and grounded.
2. WARNING: Improper use of the grounding plug can result in a risk of electrical shock.
3. Consult a qualified electrician or serviceman if the grounding instructions are not
completely understood, or if doubts exist as to whether the unit is properly grounded.
4. If it is necessary to use an extension cord, use only a 3-wire extension cord that has a 3-
blade grounding plug, and a 3-slot receptacle that will accept the plug on the unit. The
marked rating of the extension cord should be equal to or greater than the electrical rating
of the unit.
5. CAUTION: The glass vacuum chamber can become HOT when operating at pull power at
100% duty cycle. TAKE PROPER PRECAUTIONS WHEN HANDLING THE HOT
GLASS, ESPECIALLY UNDER VACUUM. DO NOT OPEN THE DOOR WHEN
THE BELL JAR IS UNDER VACUUM. THE POSSIBILITY OF IMPLOSION
ALWAYS EXISTS WITH GLASS UNDER VACUUM ESPECIALLY IF THE
GLASS IS HOT.
6. When the run is finished, shut off the vacuum pump and vent the bell jar immediately by
turning the vent valve towards the back of the unit. If the bell jar is not vented immediately
oil may suck up from the vacuum pump and contaminate the system. PLASMA-PREEN
units shipped without the Control Panel are equipped with a vent valve. The vent valve has
a 0.013" diameter flow-constricting orifice to prevent small parts from flying around inside
the bell jar during the venting operation. The gas flow is automatically shut off when the
vent valve is in the vent position.