Troubleshooting the STA Compact Service Part 1

Tutorial on determining the source of an issue for the STA Compact, Part 1: Quality Control and Precision problems. See also: parts 2, 3, 4, and 5.

A Transcription of Troubleshooting the STA Compact – Service Part 1

The STA compact. We're simulating what you would do to really find out what an issue is on any instruments. I don't care if it's a quality control or if it's the crashing needles or a gripping problem. We're going to take it from the beginning. Okay. Here's the main screen. I want to get into maintenance. (Narrator demonstrates menu, :28) So, I hit Escape, go over to Maintenance, Maintenance.(Screen change, :30) Here's my user maintenance. Alt, F10. My code for today is. (Narrator enters code, :39) Bring the first number down, a o. Second number goes to the right, and the third number goes to the left. So, next number is 0, then 3, 7. Figure out the last two numbers. I go 9, 10, 11, 7, 8, 9, 10, 21, 21. 16 goes into 21 once. So, the first letter is a one, and then I have five remainder. So, the next letter is a 5, and that should get us into the service menu.
By the way, you can only check that . . . You can only do that code twice before it'll boot you out and won't allow you to get into the service. (Screen change, 1:21) After that, you have to shut it down. Okay. Here's the service maintenance. I've got the robotics. First thing I'm going to go into for a general check is the endurance. Let's change that.

Let's go into the Fluidics first and do the Fluidics first. (Screen change, 1:41) All right. This is the Fluidics screen. I can hear my pump come on. It's always a good thing. My cleaning bottle is filled, high. Let's go over to the pumps. First thing we're going to do is check out the needles. Generally, this would be for a quality control issue. (Camera pans to the STA Compact, 2:00) All right. Let's go over to the instrument. Look at the needles. You might want to take a break here. Can you see the needles? Okay. All right. We're going to put 20 pulses into needle number one and hit "Enter". (Series of tests performed, 2:17-2:59) There's our 20 pulses. I don't know if you can see it, but the fluid is coming straight down. It's not flaring off to the side. It's going right into the well. The well didn't overflow, which is a good thing. So, the vacuum must be at least halfway working. Now, we're going to go do the same thing for needle two. We're going to put 20 pulses in it. It's a little of an angle, but that's not a big concern of mine. If it was a minor quality control, that might be a hint, but that doesn't look too bad. I'm going to do the same for needle number three, 20 pulses. Needle number three, that looks good. All coming straight down, going in the well. It's not overflowing. That seems to be pretty normal. All right. Next thing is to check really that the needles aren't restricted or defective. (Narrator moves machine arm to the right, 3:06) I'm going to take a little vile, and I'm going to put this over my waste bin here. I'm going to put another 20. By the way, you do not want to pulse these one after another too many times. You want to take a little break between them, especially if you're putting like something like 50 pulses, which you would do if you were putting in bleach or clearing the bleach out of it.
Here's 20 pulses. (Narrator places vial over needle number one, 3:32) I'm going to put my little vile over needle number one, and I'm going to hit Enter. What I'm looking for is that solution should fall in between these two lines. (Narrator holds up vial, 3:51) That tells me my Valcor pump is working, 3 mL, 4 mL. 3 mL is my bottom line. 4 mL is my top. I don't particularly care if it's too high. It's just going to be cleaning a little better. I will tell you if it's on the high side, then you might get an operator complaining of uses too much cleaning solution. It doesn't time out right. I consider that a minor problem. Bottom line, between 3 and 4 mL is specs for 20 pulses. I now know my Valcor pump is adjusted and is proper. I'm going to try the same thing for needle number two. (Narrator places vial over needle number two, 4:37) For the most part, it should be approximately the same amount. There shouldn't be a drastic difference between needle one and needle two. I'm not trying to get down to a specific, but eyeballing it, you can see that it's about the same. That's the way it should be. There's only one Valcor pump. It sends the solution through each needle. Thus, it should always be the same, pretty much. The reason I mention that is if for some reason it is not the same, it's going to be an indication of a bad needle. (Narrator places vial over needle number three, 5:12) I'm going to do the same for needle number three. Again, that's just a quick way of checking that your needles aren't clogged. If I saw a big difference in just one of them, I'd look into it. Again, you can sit there and hopefully you can see that it's about the same. So, now I know my Valcor pump is okay, and I'm pretty comfortable my needle is okay. (Narrator moves machine arm to the left and toward the rear of machine, 5:38) For the most part, I'm okay with the vacuum pump. We're going to check vacuums. A vacuum can cause you a lot of quality control issues. I've got a vacuum gauge, any gauge. (Narrator places vacuum gauge inside machine on the far left port, 5:56) There's three ports on the back. You can use any type of vacuum gauge. Just this gauge makes it real easy. I'm going to . . . Through the service diagnostics, I'm going to turn on needle number one or well number one. (Camera zooms in on vacuum gauge, 6:13) Hopefully, you can see that that goes up to eight millibar. Eight millibar is what it should be, not five, not six, eight millibar. If it's not at eight millibar, you have an issue. Now, I'm not saying it's not going to be 7.5, but it should be eight millibar. All right. Now, what I'm going to do is I'm going to go, and I'm going to turn, through my service maintenance, the fluidic circuit, I'm going to turn off my vacuum pump. I consider this to be a somewhat of important test. When I turn off my vacuum pump, you can see my needle does not drift downward. It should not. If it starts drifting downward, it would be an indication that I have a leak somewhere. Usually it's in an EV valve, but it could be in the tubing. As you can see from looking at this, it's steady, and that's as it should be. So, I'm going to turn my pump back on. I am going to close well number one, and I'm going to go to open well number two. You might be able to hear that. (Narrator moves vacuum gauge to center port, 7:18) I put my gauge over number two, and it should come up to eight millibar. Now, there's a time sequence of how fast that should come up. Quite frankly, I'm not too worried about that. I just simply want to make sure that it gets to eight millibar. Eight millibar is there. Again, I go and I turn off through the service. I turn off the vacuum pump. And again, my eight millibar should stay there, which it is. That tells me I have no leaks in wash well number rtwo. Okay. Turn it back on. We're going to go over to well number three and do the same thing. (Narrator moves vacuum gauge to far right port, 8:04) Well number three should come up, eight millibar. Now, I am now after . . . Once it gets to eight millibar, I am going to turn it off. The vacuum pump is off, and it should stay there. I now know my vacuum system is working fine.(Narrator removes vacuum gauge, 8:22) I'm going to take a second to show you one little tip. Periodically, one of the common things is for needles to get in the wash well. I usually do this every time I do a PM or if I'm having any problems crashing needles or anything like that. It's just a common thing I do because it only takes a second. I take . . . Usually it's a wooden applicator, but in this case, I'm going to use an Allen wrench. I take an Allen wrench, and I put it down inside a wash well. (Narrator places allen wrench in wash well and hold up to demonstrate depth for all three wash wells, 8:48-9:22) Put it all the way down to the bottom. I dig my finger so, I know how I mark it. This is how far that Allen wrench went into the wash well. It should be the same for needle number two. It shouldn't go down further. It should go down the same amount. I will tell you if you use a wooden applicator, wash well number one is a little skinnier way down there in the bottom. So, you can't use a wooden applicator.

The bottom line is all these should be the same distance. If they're not, they've got a BB stuck in them, which would cause two issues:
crashing needles possibly, possibly intermittent, and the wash well will overflow. That's probably number two reason for wash well to overflow, would be the BBs. Number one would probably be the EV valve. (Narrator moves machine arm to the center of the machine, 9:37) EV valve is something I would recommend keeping a spare of.