RollaJase's Trip Off the Deep End - Custom Rimless 55G

[jedimasterben]

Hmm, I see, thanks for explaining that. I'm using all the channels individually with channel 1 & 2 sharing whites and channel 3 & 4 sharing the blues. So, realistically I could have channel 1 & 2 controlled from a single slider in the BF mini and I could do the same for channel 3 & 4, good to know. You couldn't see anything wrong with how I have things set up?

No, beyond that you could control 1/2 and 3/4 from two channels instead of four, just pull the jumpers for CH2 and CH4, then place a jumper on one set of pins from 1-2 and from 3-4.

[Benny314]

Some channels powered on......... do you mean slightly glowing or running 100%?

 

I'm sure Ben may have ruled this out already, but have you checked the pull down resistors for the affected channels on the LDD board? If those 10k resistors are cooked the LDDs will default to 100% output when they have a zero PWM input.

[RollaJase]

No, beyond that you could control 1/2 and 3/4 from two channels instead of four, just pull the jumpers for CH2 and CH4, then place a jumper on one set of pins from 1-2 and from 3-4.

Thanks Ben, I'll have a play with this. Makes sense to link the identical channels together.

 

Some channels powered on......... do you mean slightly glowing or running 100%?

 

I'm sure Ben may have ruled this out already, but have you checked the pull down resistors for the affected channels on the LDD board? If those 10k resistors are cooked the LDDs will default to 100% output when they have a zero PWM input.

What I initially tested for was fried drivers. When I tested each channel it was without the channel select jumpers installed therefore bypassing the pull down resisters. I then tested the SCW drivers for faults and to make sure the arduino and bluefish powered on. I didn't get so far as to test each channel individually for faults, I was going to hang the light and look at each array then (as it is easier). Correct, all channels during testing turned on at 100% (besides channel 6, still not working). When I installed the bluefish some channels remained at 100% (blues from what I can tell) while I was unable to control any channel from the bluefish.

 

I agree, I've probably damaged some of those resisters also. When looking at them, two are very close together which could have caused arcing if one failed, the others have good spacing. None of them are visibly burnt out. Guess I've got to bust out the multimeter again and possibly replace some resisters.

[RollaJase]

Resistors are fairly cheap, now I just need to find a suitable replacement. Kinda hard when I have no idea what I'm shopping for lol. I figure if I have to replace one, I may as well replace all 6 for piece of mind. SMD chips are fairly easy to solder, just requires a steady hand and some tweezers.

 

Looking at a zoomed version of the jumper picture I posted on the previous page it looks like the resistors on channel 5 and 6 are actually touching at the solder point on the jumper side of the resistors. This could be contributing to my issues with channel 6 acting weirdly.

[Benny314]

Think you'll find they're 10k 1206 SMD.

 

These look right.

http://www.aliexpress.com/item/1206-SMD-Resistor-5-10K-ohm-5000pcs-lot/32307467056.html?spm=2114.30010308.3.11.B9L8ra&ws_ab_test=searchweb201556_0,searchweb201602_5_10037_10017_10021_507_10022_10032_10009_10020_10008_10018_10019_101,searchweb201603_7&btsid=3f8a604c-364e-467d-99e0-213d2ac52f51

 

The trick is getting SMD stuff back off lol. I ended up flicking resistors across the room when using a bamboo barbecue skewer to push them off the pads as I melted the solder both sides. Soldering down isn't too bad if your steady with the soldering iron.

[jedimasterben]

I love how 100 of those are $0.69 lol

[RollaJase]

Think you'll find they're 10k 1206 SMD.

 

These look right.

http://www.aliexpress.com/item/1206-SMD-Resistor-5-10K-ohm-5000pcs-lot/32307467056.html?spm=2114.30010308.3.11.B9L8ra&ws_ab_test=searchweb201556_0,searchweb201602_5_10037_10017_10021_507_10022_10032_10009_10020_10008_10018_10019_101,searchweb201603_7&btsid=3f8a604c-364e-467d-99e0-213d2ac52f51

 

The trick is getting SMD stuff back off lol. I ended up flicking resistors across the room when using a bamboo barbecue skewer to push them off the pads as I melted the solder both sides. Soldering down isn't too bad if your steady with the soldering iron.

I thought so too, but the code silkscreened to the top of the SMD is *S4 (the ' * ' being something I can't read). I couldn't find anything that corresponded to that on a standard code list. I'm going to take a HD picture tonight with my DSLR to take a closer look.

 

Removing them is a pain yes. Seeing as I don't care if I fry them while removing them I'll just lay the solder tip across the length of the resistor heating both sides at once while I lift with some tweezers.

I love how 100 of those are $0.69 lol

Have you ever had to replace any of the resistors on your O2 boards Ben?

[jedimasterben]

No, I've never had any resistors fry, but i have a variable temp reflow heat gun to use for little things like that. I believe in the past I did do it once with a soldering iron for something small and SMD like that, and it worked decently, should be especially fine since you're replacing them.

[RollaJase]

No, I've never had any resistors fry, but i have a variable temp reflow heat gun to use for little things like that. I believe in the past I did do it once with a soldering iron for something small and SMD like that, and it worked decently, should be especially fine since you're replacing them.

Ah fair enough. If I did this type of soldering more frequently I'd probably get a re-flow gun also. I think I may as well replace all 6 if I have fears that one of two may be damaged. For the cost of them, it just makes more sense. Now I just need to track down the right part and then order some online.

[RollaJase]

I only just realised, looking at some pictures of the board, that under each LDD driver there is a resistor which is labeled '10K'. There are also a set of 6 resistors that sit between the BF mini pins and the channel enablement pins. Those are the resistors I thought we were talking about lol. That makes life a little easier. The resistors next to the BF mini pins are the ones I spotted some potential damage with. I might just replace both sets.

[Benny314]

Yeah the ones I'm on about will be under the LDDs. I didn't say that's where they were as some boards put them else where, but if you look at the trace the resistors go between the PWM pin and the ground.

If there's a zero signal from the controller PWM the resistor allows the current to escape to ground, if you remove the resistor the LDD defaults to 100% when it has no input signal.

So if your always on channels are at 100% I would suspect a bad resistor or issue in that pull down loop. If the channel is glowing it could be an issue with the signal from the controller not going to zero.

I'm not a 100% but I would think the resistors between the controller connection pins and the board have something to do with preventing the controller getting fried by feedback or issues with a driver. But I'm not 100% on that level of electrical know how.

[RollaJase]

Yeah the ones I'm on about will be under the LDDs. I didn't say that's where they were as some boards put them else where, but if you look at the trace the resistors go between the PWM pin and the ground.

If there's a zero signal from the controller PWM the resistor allows the current to escape to ground, if you remove the resistor the LDD defaults to 100% when it has no input signal.

So if your always on channels are at 100% I would suspect a bad resistor or issue in that pull down loop. If the channel is glowing it could be an issue with the signal from the controller not going to zero.

I'm not a 100% but I would think the resistors between the controller connection pins and the board have something to do with preventing the controller getting fried by feedback or issues with a driver. But I'm not 100% on that level of electrical know how.

Thanks for your input, glad we are on the same page now haha. Yeah, I'm no electrical wiz, especially when it comes to circuits but I do understand a little bit about how resistors work/function. I'd imagine that the resistors between the bluefish and the pins have a similar function to what you think also. I might leave those ones for now and just replace the ones under the LDD drivers first. I'm assuming they are all the same resistors, if so I'll just replace the lot.

[Benny314]

Yeah should all be identical if they're all marked 10k. Think there's different sizes of SMD resistors and capacitors, but the markings on them (especially the cheap Chinese ones) aren't all identical. The same resistors might have different numbers based on manufacturer.

Like I said, first glance I think 1206 SMD is the right size, so we know the LDD pull down resistors will be 10k, it'll just be finding out what the ones between the board and the controller are from the markings on them (probably 10k).

[RollaJase]

Yeah should all be identical if they're all marked 10k. Think there's different sizes of SMD resistors and capacitors, but the markings on them (especially the cheap Chinese ones) aren't all identical. The same resistors might have different numbers based on manufacturer.

Like I said, first glance I think 1206 SMD is the right size, so we know the LDD pull down resistors will be 10k, it'll just be finding out what the ones between the board and the controller are from the markings on them (probably 10k).

All the 10k resistors are the same with the exception of one, all of which look to be undamaged. The ones between the board and controller however I don't think are resistors, they are much thicker than the 10k ones but you can see from the pictures below why I am concerned with them. The two on the far left look to be touching on the solder point closest to the jumper, the two on the far right are in a similar situation.

 

 

So, sciency lesson time kids, time to learn something.

 

10k Resistors:

One reads 103, the others are 1002. These numbers are supposed to represent the resistance value of the particular resistor. There are different ways to decipher this code depending on whether it is a 3 digit or 4 digit string. For example, 103 is read as 10 x 10 to the power of 3 which equals 10,000, so it's a 10K resistor. 1002 is read as 100 x 10 to the power of 2 which also equals 10,000, another 10k resistor. So, all the resistors associated with the LDD drivers are 10k which was to be expected. After measuring the length of the longest side of the resistors (3.2mm) and the short side of the resistors (1.6mm), I can also safely say that they are 10k resistors of 1206 sizing (3216 metric). I believe they are also of the 'Thin Film' design of SMD resistors.

 

Looks like this will be a suitable replacement for any damaged 10K resistors. Sold in quantity of 5 for roughly $0.50 per resistor. The cheapest Thin Film resistor I can get through Element14/Farnell that isn't sold in quantity of 100's or 1000's.

http://au.element14.com/bourns/crt1206-by-1002elf/res-thin-film-10k-0-1-0-125w-1206/dp/2008319

 

What is between the controller socket and the jumpers:

These on the other hand, I'm not sure about at all. I doubt they are causing any trouble but the soldering of the outer pairs concerns me somewhat. I think they may be a 'Thick Film' resistor of some type but the value remains a mystery to me. I can't make out the first digit on any of them (if there is one), even with a close up picture but the other digits read either 34 or even 84 from what I can tell. I believe the identification method on these resistors to be the newer EIA-96 method which isn't widely adopted yet. Using the EIA-96 method, the code 34 references to 221 which is 22 x 10 to the power of 1 equaling 220. Whereas code 84 references to 732 which is 73 x 10 to the power of 2 equaling 7300. Obviously, neither of which equal 10k.

 

Not sure what I'll do about these other ones but I'll probably order the 10k resistors while at work tomorrow.

[Benny314]

Could be diodes. I believe diodes prevent the wrong direction of current flow to protect things the other side.

[RollaJase]

Could be diodes. I believe diodes prevent the wrong direction of current flow to protect things the other side.

After I posted the above I got to thinking about that also. I sent an email off to the guy who makes these boards, hoping he can confirm what they are and what spec they are so I can order some replacements with the resistors. I figure if I am busting out the soldering iron and I have some concerns with them then I may as well just replace them also.

[jedimasterben]

They are resistors put in place to protect the BF Mini in a 'shit hits the fan' case lol. The production Mini comes with resistors on it, but when O2 was designing the board he put them on since he was using a beta Mini that did not have the resistors.

[RollaJase]

They are resistors put in place to protect the BF Mini in a 'shit hits the fan' case lol. The production Mini comes with resistors on it, but when O2 was designing the board he put them on since he was using a beta Mini that did not have the resistors.

Ah, thanks for the clarification Ben. I think my situation falls under the 'shit hits the fan' category lol. I'm just waiting for O2 to confirm the value of said resistors and I'll replace them anyway. Can never be too safe I guess haha.

[Benny314]

They are resistors put in place to protect the BF Mini in a 'shit hits the fan' case lol. The production Mini comes with resistors on it, but when O2 was designing the board he put them on since he was using a beta Mini that did not have the resistors.

 

If the BF has the resistors on board, just remove them from the LDD board and put jumpers on instead. Be easier to get a jumper soldered in there than new resistors. Looks tight between the headers.

[RollaJase]

 

If the BF has the resistors on board, just remove them from the LDD board and put jumpers on instead. Be easier to get a jumper soldered in there than new resistors. Looks tight between the headers.

This is also a possibility, I'd rather not modify the design on the board though. The added protection of having those resistors there just in case seems like a good idea to me. Yes, soldering may be a bit of a pain though, just need to be careful I guess.

[RollaJase]

So, still nothing from O2 via email but I just had a brain wave. If the BF mini has resistors on the board itself, I should be able to read the values from those to know which replacements i need for the driver board. The resistors on the BF mini read 89A which is a 825ohm resistor, a 125mw model should suffice. So, in the off chance that I'm correct, I'm going to order some resistors at this value also while I wait for O2 to respond.

[RollaJase]

I heard back from O2 over night, he was away on vacation but set me straight with what I need to fix the driver board. Turns out the resistors/diodes that I couldn't identify were SCHOTTKY barrier diodes (rectifiers). As Ben pointed out, these are there to protect the BlueFish Mini in the event that something goes really wrong and feedback travels back to the BF mini. I'll be replacing all 6 of these to be safe.

 

The 10K resistors that I ordered arrived this morning. Luckily, half of the other items I ordered with these resistors are on back order so I'm hoping that I can add the SCHOTTKY diodes to the order while removing the 825ohm resistors as they are not required.

 

I may also be unlucky enough that the Arduino is damaged. For the sake of $8, I just ordered a new one to be safe. O2 provided me with a copy of the fan control software so I can load it onto the new Arduino.

 

I'll be very happy to have this issue fixed, looks like i'm on the final stretch now .

[4x5]

How things going with this beast?

[RollaJase]

How things going with this beast?

Hey Shaun, how's things? Slow and steady over here and well over due for a serious update. I had my new light over the tank for no longer than a week before blowing it up so I'm trying to get all that sorted out right now. Lucky for me I hadn't sold my old light yet. I'm hoping that the last piece I need to fix the light will arrive this week so I can finally get that back up an running and snap some photos for a serious update.

[4x5]

Good thanks man. Busy but good times all round. I accidentally redid my tank this weekend, went to the store to get some snails came home with new rocks. Woops. Looking forward to the update.