Viscometers Using Light-Barrier Sensing; Connection Of Vz 7215 Absorption Traps - Fisher AVS 470 Manual De Instrucciones

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2.3.2

Viscometers using light-barrier sensing

Use the hose/cable combination to make an electrical and pneumatic connection between the AVS 470
Viscosity Measuring Unit and the measurement stand. The plugs are firmly connected to the sockets by
rotating the union sleeve. Please observe the colour codes (red = sucking, black = venting) when screwing
the threaded pneumatic connections into the ViscoPump II module.
Please insert the selected capillary viscometer into the fixating rack as is shown in fig 4., then fill it. Insert the
fixating rack together with the viscometer into the measurement stand (with the cut-out at the bottom sheet
pointing forwards). The cut-out will latch into the lug provided. Pressing the viscometer slightly against the
fixating rack will latch it into the holding spring located on the measurement stand.
Fig. 4 Inserting or replacing a viscometer with light-barrier sensing
2.3.3

Connection of VZ 7215 absorption traps

In the "sucking" mode (vacuum), the solvent will become volatile and then condense within the system; in
the case of oil applications, other volatile components, for instance, graphite grains, may reach the interior of
the ViscoPump II module where they can lead to solid deposits.
A PTFE hose combination in "suction" design was developed for cases of this kind. Its primary range of
involves applications having to deal with dichloracetic acid, formic acid, with sodium lime serving as an
absorption agent. In other cases it is possible to use other absorption agents (preferably activated carbon).
If the above influences are present, the VZ 8524 hose kit or the VZ 7215 absorption traps MUST be
used!
The absorption traps which prevent contaminations from penetrating into the pneumatic system of the
ViscoPump have to be inspected at regular intervals. If sodium lime is used as an absorption agent with
acidic solvents, the colour condition of the indicator is to be checked on a daily basis. As soon as this
condition has shifted to BLUE in the half of the absorber material, this is the very last moment to replace the
material for safety reasons.
Please note: If such a colour shift will not be observed over an extended period of time, this may be
attributable to the fact that an acidic over-saturation of the material has caused a de-colouration; this may
then appear as "normal", but it will definitely result in the destruction of the pneumatic system after some
time. This situation is explicitly excluded from the warranty coverage!
When using activated carbon as an absorption agent (e.g. with solvents or used mineral oils), a replacement
should be made at intervals between 1 and 2 weeks; this depends on the load factor which, in turn, is a
function of the volatility of the materials.
Chapter 2 initial operation