Roche MagNA Pure Compact Instrument, Operator'S Manual

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Maintenance and Trouble Shooting 75
C
C
1.2 O-ring Maintenance
Purpose of O-rings: The O-rings hold the reaction tips on the nozzles of the Nozzle Head.
They also form an airtight seal around the top of the reaction tips to prevent leakage and
ensure accurate pipetting. After a time, O-rings may wear out and cause the reaction tips
to either leak or be poorly attached to the nozzles. Therefore, worn O-rings can eventu-
ally lead to pipetting errors.
1.2.1 Greasing the O-rings
Lubricating the O-rings prevents them from deteriorating (e.g. cracking) and allowing
the reaction tips to leak.
The O-rings should be greased regularly, whether the instrument is in use or not. You
should grease the O-rings once a week or after each 20 purification runs. Also, to ensure
correct reaction tip function, you must lubricate new O-rings before placing them on the
pipet nozzles (as in Section C.1.1.2 below).
Procedure for correctly lubricating the O-ring:
Note:
We advise checking O-ring lubrication periodically and adding small amounts of vacuum
grease as needed.
Never use bleach or ethanol to clean the Nozzle Head. These reagents will remove grease
from the O-rings and probably even accelerate the deterioration of the O-rings them-
selves. We do not recommend ever using these reagents to clean the Nozzle Head.
In case the Nozzle Head has to be cleaned, remove the O-rings beforehand. Having
cleaned the Nozzle head, apply bi-distilled water and put the greased O-rings back to
their proper position.
Apply a small bit of vacuum grease to index finger, then rub it between thumb
and index finger.
Note: We recommend that you use special High Vacuum Grease. A tube of this
grease is supplied with the instrument. To order replacement tubes, see the
Recommended Products section in chapter C.
Rub the O-ring with your greased fingers.
Remove excess vacuum grease from the O-ring with a cloth ( e.g. Kimwipe
TM
).
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User Maintenance
O-ring Maintenance
MagNA Pure Compact Manual.book Seite 75 Dienstag, 28. Februar 2006 4:16 16