Overlapped injections - Solved!
Posted: Fri Apr 27, 2007 5:54 pm
Both Sniff and I have had problems trying to get PAL autosamplers to perform overlapped injections with Agilent 1100s and 1200s, where the autosampler moves the syringe to pick up a sample and bring it to the injection port while the previous injection is still running. This means that when the first injection finishes, it can immediately start the next injection instead of waiting for the autosampler to go through its routine, saving around 20 seconds or so per run. (If you're making injections every 2 minutes or so in a high throughput environment, 20 seconds is a big deal.) You can have the Enable Overlapped Injection button selected in Chemstation, but when it reaches the designated timepoint the arm just shifts position slightly and sits there waiting for a signal to proceed. It doesn't actually begin the routine until the previous injection is over, and therefore doesn't overlap at all.
The solution to the problem is in the handheld PAL controller.
Go to Menu
Press Setup
Press F3 (nothing shows on the window for F3, this is kind of an Easter Egg which allows access to features otherwise unavailable)
Select Objects
and then Sync Signals
The one you want is Start
The default seems to be TTL-ln1, change this to Immediate and then Home to exit the function.
And now you are ready to rock, high-throughput style!
The solution to the problem is in the handheld PAL controller.
Go to Menu
Press Setup
Press F3 (nothing shows on the window for F3, this is kind of an Easter Egg which allows access to features otherwise unavailable)
Select Objects
and then Sync Signals
The one you want is Start
The default seems to be TTL-ln1, change this to Immediate and then Home to exit the function.
And now you are ready to rock, high-throughput style!