Teledyne 4250, Installation And Operation Manual, Page: 98 / 204

4250 Flow Meter
Section 3 Installation
3-8
You can also panel-mount the flow meter, using the mounting
bracket on the top rear of the case, or suspend it from a ladder
rung using the optional suspension bracket. To use the bracket,
the carrying handle should first be installed on the flow meter as
described above. Then slip the handle through the suspension
bracket.
Figure 3-3 4250 Suspended by Handle (handles may vary)
3.3.4 Vent Hose to Desiccant
Cartridge
If you suspend the flow meter above the flow stream and there is
any possibility of accidental submersion, attach several feet of
vinyl tubing to the open vent on the end of the external desiccant
cartridge. You should route this tubing to a place higher than the
maximum possible level of the flow stream. This will prevent any
water from entering the vent tube of the AV sensor in case of
accidental submersion of the flow meter. Vinyl tubing can be pur-
chased locally or from Teledyne Isco.
If you use the Quick-Disconnect Box to extend the distance
between the flow meter and the sensor, attach the vinyl tubing to
the desiccator cartridge vent on the Quick-Disconnect Box rather
than the vent on the flow meter. (Presumably the flow meter is
mounted safely away from the flow stream if you are using the
Quick-Disconnect Box.) If you cannot mount the Quick-Dis-
connect Box far enough above the flow stream to ensure against
accidental submersion when the flow stream is high, you should
protect the desiccator and the reference port by venting them
with vinyl tubing to a point the water cannot possibly reach.
Remember that water or other blockage inside the sensor’s vent
tube can ruin the sensor. It is even more important to protect the
Quick-Disconnect Box than the flow meter, because the AV
sensor will be directly attached to the Quick-Disconnect Box.
When connecting the sensor to the flow meter, you may use an
extension cable, which would offer some protection to the sensor.