Whenever you use the DOS graphical scheduler, it automatically tries to spread the amount over the longest possible time. This is in an effort to reduce spikes in parameters, to reduce wear on the pumps, and to reduce noise levels.
However, if you really want to dose a specific volume as quickly as possible, you can skip the graphical scheduler and instead manually program it with a DOS Profile and some code.
1. Create a DOS profile containing the settings for the volume you want, the pump speed, and the number of doses. This example will deliver a single 20 mL dose at the pump rate of 125 mL/minute (that's the 2nd fastest rate possible, but if you choose 250 mL/min it will be extremely loud), which will only require the DOS to run for 9.6 seconds for 20 mL:
2. Then in the DOS schedule, click the gear at the top right, then click the Advanced tab. Here you can enter program code which overrides the graphical schedule. Here's an example to do a single 20 mL dose every day at 8:00am:
Set OFF
If Time 08:00 to 08:01 Then DOS_20ml
Because of the Set OFF command, the DOS will remain off at all times except for 8am when it activates your custom profile. The settings in the graphical scheduler will be completely ignored.
Read the DOS User Guide for more details on DOS profiles:
For more Apex tips and examples, see my series of Apex tutorials:
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