Diluters and Dispensers
All of the diluters and dispensers are made in the same basic format. They are all built with an aluminum frame with a clear polycarbonate front piece that holds the glass valves and have a handle manually moved through a set arc that draws up or expels solution determined by the configuration of the glass valves, tubing, probes, and plastic syringes.
To adjust the syringe volumes, allow the handle to remain in the up, stop position. Loosen the wing nut on the syringe barrel bracket and the round thumbscrew on the bottom of the syringe plunger anchor. Move the syringe anchor up the rod toward the front for larger volume and down or toward the back for less volume. Push the syringe barrel down so that the plunger head is at the top of the syringe. Tighten the thumbscrew and wing nut and check the volume by pushing the handle to the down position.
Follow this complete procedure for each volume change.
Failure to adjust volumes in this manner will cause pressure to be applied to the syringe barrel bracket. The volumes indicated on the syringe are nominal rather than exact. For dilutions, a nominal value is usually sufficient since standards should be prepared so that they will be diluted in the same manner as the unknown. The standard curve will then account for the dilution factors. If exact dilutions are desired, then a standard solution should be diluted by hand pipet and the value checked by spectrophotometer or AA, then the volumes on the diluter can be adjusted to match the hand pipet dilution