Datawell BV Hippy 40-MkII, Руководство пользователя

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12 Maintenance and repair
In case of underpressure the lid can be lifted by using the threaded hole and one of the screws.
See fig. 7 below.
fig. 7
Location of components (see fig. 6 and 8) 12.1
The sphere which contains the stabilised platform is placed in a cylinder of hard foam at the
bottom of the can.
The electronic circuit board, together with two bags of silicagel, are placed in a polyethylene
bag and clamped between foam rubber cushions between the lid and the hard foam cylinder.
Connections between pcb and junction box are via an octal plug through the lid which is airtight
closed.
Fixed under the lid and isolated from it, is a screen which is connected to 0 (common of pitch
and roll output) via a plugged brown lead.
Humidity 12.2
The can is hermetically closed, so no humid air can enter the can from the outside.
The fluid in which the stabilised platform is suspended however contains water which can
diffuse very slowly through the wall of the sphere. To prevent a 100% relative humidity and
condensation, two 65 gram bags of silicagel are inserted in the polyethylene bag which contains
the electronic circuit board.
This is sufficient to keep the relative humidity low for at least two years, provided the
polyethylene bag is carefully sealed with tape.
Relative humidity is roughly indicated by a strip (visible through polyethylene bag) which fades
from blue to pink if relative humidity exceeds 40%.
If relative humidity is too high, renew silicagel or dry at max. 110°C for at least
12 hours.
If silicagel is inserted in the polyethylene bag take care:
1)
To prevent direct contact between silicagel bags and pcb (see fig. 6).
Place silicagel bags in special compartment within polyethylene bag!
2) Seal bag carefully with tape, especially where the leads enter the bag.
3) Replace pcb roughly in the same position with regard to can as before.