Dismantling Procedure - Techne SBS-2 Manual Del Operador

DISMantlIng prOCeDure

In the following steps refer to the wiring diagram included in this manual:
To expose the energy regulator, fail safe switch, and electrical wiring, proceed as follows:
Disconnect electrical and air supplies, empty the bath medium. Turn the bath upside down.
Unscrew the hex nut holding the base plate and carefully lift the base plate.
Disconnect all flying leads between the baseplate and the main case at the terminal block on the
baseplate.
replacement of heater and porous plate.
Follow the steps described above.
Remove the whole stud assembly by unscrewing the lock nut.
Disconnect the heater wires from the terminal block mounted on side of outer case. Tag the leads so that
they can be connected to the right terminals.
Unscrew the gate valve.
If the thermocouple is installed in the thermocuple well, remove it.
Slowly lift the outer case upwards. The whole inner assembly will now be exposed.
Tape the top rim to the inner bath.
Removal of the fiberglass insulation will expose the heater wire connections and lock nuts. To remove
individual heaters, remove the appropriate link wires from the terminal ends and then unlock the nuts.
From the outside of the container, squeeze the heater limbs together which will in turn withdraw the
heater ends from the holes.
To replace the center heater it will be necessary to remove the top one first. To replace the bottom heater
it is advisable to remove the porous plate first and work from the bottom. (SBS-4).
On models with a stainless steel porouos plate (SBS-4), removal of the porous plate is done by removing
the haxacon screws and nuts and lifting off the air chamber.
On replacing a porous plate the peripheral edge must be sealed with a glass solution (sodium silicate)
after clamping up the screws.
On models with a ceramic porous plate (SBS-2) remove the porous plate by using a sharp knife to
separate the gasket either from the porous plate or the inner bath. Use a long screwdriver to lift the
plate. Avoid damaging the inner bath. Since the porous plate will be replaced, do not concern yourself
if the porous plate gets damaged. After the porous plate is removed, thoroughly clean the inner bath
and remove the remaining gasket material adhering to the bath. If the porous plate support is damaged
(SBS-2), replace it. Put a bead of RTV 106 around the inner periphery just above the air inlet tube,
approximately 3/8 inches wide. Be sure not to block the air inlet tube. Lay the porous at the top of the
inner tank and slowly push the plate downwards. Make sure the plate is always horizontal. Push it all the
way down as far as it can go. Let the RTV cure for 24-48 hours.
Reassemble in reverse order to that stated above. It is important that the fiberglass insulation is retained
closely to the inner container by either wire bands or fiberglass rope, thus allowing an air gap between
the insulation and the outer case.
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