About Dispensing and Cleaning Steps of the Bottle-Top Dispenser

The bottle-top dispenser allows operators to dispense liquids from bottles directly. The instrument can be adjusted to various bottles using the adapter. Always follow instructions in the operating manual of the dispenser as well as the reagent manufacturer’s speciffications. If used with strong acids, it is advised to rinse & remove dispenser at the end of every working day & store it safely. If you require information on chemicals not listed, please contact HAWACH(email: pipette@hawach.com).

1.1 Precautions
Which liquid is to be dispensed? Observe the application exceptions. Place a suitable collecting vessel underneath the tube. Wear eye protection, protective clothing, and protective gloves. The discharge tube must always be pointing away from the user and any other persons. Follow the general safety instructions.

1.2 Air Removal
Take off the drip-catcher. Place a suitable collection container under the discharge tube, pull a little up piston and press down. Repeat the movement in the lower filling area (2-3 cm) of the cylinder. Stops when there are no air bubbles in the cylinder. Move the lever and press down the piston slowly. Then set the lever back and return the liquid that is still inside the cylinder to the bottle.

1.3 Volume Setting
Turn the volume setting screw a little counter-clockwise. Aim the pointer at the desired volume and then re-tighten the volume control screw.

1.4 Dispensing Operation
Take off the drip-catcher. After emptying the air and setting the volume, place the fixed collecting container below the outlet of the discharge pipe. Slowly and steadily pull the piston all the way up and then press the piston down to discharge the reagent drawn into the glass cylinder into the vessel.
CAUTION! The tube may drip! Keep the piston low and push the drip collector onto the drain line. If the piston is difficult to move, stop immediately and clean the instrument.

0.1~99.9mL Electronic Bottle-Top Dispenser

2.1 Standard Cleaning
The instrument must be cleaned immediately in the following cases:
The piston is difficult to move; change of reagents; after lengthy periods of non-use; before any maintenance and repair work; before sterilization.

2.2 Preparations for Cleaning
Wear eye protection, protective clothing, and protective gloves. Avoid splashing of reagent.
(1) Place the screwed-on instrument together with the bottle in a washbasin.
(2) Move the lever to the Return set.
(3) Empty the piston by pressing it down.
(4) Unscrew the instrument from the bottle. Then pull out the instrument until the intake tube is no longer immersed in the liquid.
(5) Place the inlet pipe against the inside of the bottle carefully until the reagent is expelled from the inlet pipe.
(6) Lift the instrument of the bottle.
(7) Set the lever to dispense.
(8) Keep the drain tube above the top of the bottle and return all remaining reagent to the bottle.

IMPORTANT! During cleaning or bottle change, the reagent is still present in the discharge tube even in the Return setting; after emptying the piston, set the lever to Dispensing so that the discharge tube can be emptied.
WARNING: Avoid injuries due to chemicals! The instrument, intake tube, and discharge tube may still contain reagents, so never point the opening towards the body! Wear eye protection, protective clothing, and protective gloves.

2.3 Cleaning Process
(1) Choose a suitable cleaning solution to immerse the intake tube. Clean it by repeated dispensing of the maximum volume.
(2) Move the lever to the Return setting and also rinse out the return duct.
(3) Use a pure solvent (e.g. distilled water or acetone) for repeated further dispensing.
(4) Take the intake tube out of the solution and empty it by pumping several times.

2.4 Intensive Cleaning
Before disassembling the instrument, carry out standard cleaning! Wear eye protection, protective clothing, and protective gloves. Avoid splashing of reagent.
(1) Move the lever to the Return setting and then detach it in the upward direction.
(2) Pull out the discharge tube.
(3) Pull out the discharge valve.
(4) The adjusting cap, piston bearing, and piston can be completely removed by unscrewing.
(5) Apply the tool to the stop ring and unscrew the latter from the protective sleeve.
(6) Pull off the outer sleeve in the upward direction.
(7) Unscrew the intake valve using the tool. CAUTION! The ball might drop out.

Clean the instrument with a soft brush and appropriate detergent. Then reassemble the instrument in the reverse order. Ensure that the actively sealing piston is not damaged. Set the adjusting cover so that the raised rod is aligned with the raised rod of the piston bearing. Check the instrument operation and tightness.
WARNING: Never use force to disassemble and reassemble the instrument!