Stamoclean CAT430
Maintenance
Hauser
27
7.1.5
Rinsing the sample hose between control box and measuring
devices
In the course of time, a coating also builds up in the sample hose between the control box and
measuring devices, that can result in nitrification and slurring effects. Consequently, this leads to
incorrect measurement results.
This is especially the case for the version with compressed air sample transportation.
To prevent these effects, the filtrate hose must be rinsed approx. every 6 weeks (PE hose) resp. every
3 months (PTFE hose) with a 30% H
2
O
2
(hydrogen peroxide) solution.
#
Warning!
Highly corrosive!
Be sure to wear protective gloves and protective goggles when handling hydrogen peroxide.
To rinse the sample hose, proceed as follows:
1.
Pull the hose out of the collecting vessel and insert it into a plastic bottle. Secure the hose with
an adhesive strip to stop it jumping out of the bottle.
2.
Disconnect the suction hose from the plug-in connector of the pump and insert it into a 500
ml (17 fl.oz.) bottle with the H
2
O
2
solution.
3.
Leave the CAT430 to run for 20-30 minutes with H
2
O
2
.
4.
Then reconnect the suction hose to the plug-in connector of the pump.
5.
Leave the CAT430 to run for another 20 minutes with filtrate, until the H
2
O
2
solution has been
completely removed from the system.
6.
Finally, insert the sample hose back into the collecting vessel.
7.2
Repairs
The repairs that have to be carried out on damaged CAT430 components are described below.
#
Warning!
Work on electrical components must only be carried out by authorised and trained technical
personnel.
Before beginning work, switch the factory-fitted fuses for the complete machine off.
7.2.1
Replacing a filter element
The filter element membranes have a service life of approx. 2 years, depending on operating
conditions. After this time or in case of mechanical damage, the membrane becomes permeable to
contamination. This can be detected by turbidity of the sample and by strong soiling in the relevant
PVC filtrate hose or in the corresponding duct of the filtrate Y-piece in the control box. In this case,
the defective filter element(s) have to be replaced.
Proceed as follows:
1.
Switch off "Control" on the connection box.
2.
Pull the filter unit out of the water and rinse the entire unit thoroughly with a jet of water.
3.
Check the membranes for mechanical damages, such as scratches, cracks or separations of the
membrane layer from the carrier layer. In these cases, you must replace the filter element.
4.
Pull the filtrate hose of the affected filter element out of the threaded elbow joint on the reverse
side of the element.
Press the retaining ring of the hose gland against the pull out direction of the tube.
5.
Loosen both PVC screw caps on the front side of the element.
"
Caution!
Do not allow the coupling nut or filter element to fall into the activated sludge basin.
6.
The defective filter element can now be easily removed and replaced with a new one.
7.
Mount the new filter element as described in Chapter "Installation instructions".
