PWMSlope Behavior
Re: PWMSlope Behavior
nanotrevor is having a hard time with pucks.
In my opinion, the way the pucks were designed is wrong, but that's just me. They may think the same thing of my controller design.
The issue he's having is exactly because of the - from RA connecting to LED string directly. The LED string is a high side of the driver and creates disturbunces and noise that is carried to the RA, causing it to lock-up or present weird behaviors.
I'm working with him on trying to isolate the 2 sides with opto-isolators, which should take care of his noise problem.
In my opinion, the way the pucks were designed is wrong, but that's just me. They may think the same thing of my controller design.
The issue he's having is exactly because of the - from RA connecting to LED string directly. The LED string is a high side of the driver and creates disturbunces and noise that is carried to the RA, causing it to lock-up or present weird behaviors.
I'm working with him on trying to isolate the 2 sides with opto-isolators, which should take care of his noise problem.
Roberto.
Re: PWMSlope Behavior
Well, you can mark Recom drivers as compatible with your design. I do have some isolation built into my PCB, but nothing unusual that you wouldn't expect any novice to design in.
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Re: PWMSlope Behavior
Hmm gotcha. Would it be better to build that circuit they describe on the wiring diagram in order to have them run in a non-inverted state?rimai wrote:nanotrevor is having a hard time with pucks.
In my opinion, the way the pucks were designed is wrong, but that's just me. They may think the same thing of my controller design.
The issue he's having is exactly because of the - from RA connecting to LED string directly. The LED string is a high side of the driver and creates disturbunces and noise that is carried to the RA, causing it to lock-up or present weird behaviors.
I'm working with him on trying to isolate the 2 sides with opto-isolators, which should take care of his noise problem.
-Ralph
DVRC's Mantis Shrimp Addict
15g display/7.5g sump - G. Chiragra & G. Viridis | 35g build in progress - future O. Scyllarus
DVRC's Mantis Shrimp Addict
15g display/7.5g sump - G. Chiragra & G. Viridis | 35g build in progress - future O. Scyllarus
Re: PWMSlope Behavior
I don't think that would solve the issue. The biggest problem is connecting the LED- to RA ground.
Roberto.
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Re: PWMSlope Behavior
if its wired with a transistor there is no - led connection. i tried it, i have the parts but didn't have any luck, i wired the other way cause it was quick and worked with the code inversion...but this would prob solve all probs to wire this wayrimai wrote:I don't think that would solve the issue. The biggest problem is connecting the LED- to RA ground.
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Re: PWMSlope Behavior
The picutre above would never work the way it is.
The signal LO/HI needs a ground reference, which isn't represented in the design.
The signal LO/HI needs a ground reference, which isn't represented in the design.
Roberto.
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Re: PWMSlope Behavior
hmm, prob why it didn't work for me, i thought i wired it wrong somehow.rimai wrote:The picutre above would never work the way it is.
The signal LO/HI needs a ground reference, which isn't represented in the design.
Re: PWMSlope Behavior
Can you post your schematics?icecool2 wrote:Well, you can mark Recom drivers as compatible with your design. I do have some isolation built into my PCB, but nothing unusual that you wouldn't expect any novice to design in.
I'm interested to know how you connected the RA GND to your drivers.
I'm starting to think I originally led nanotrevor into the wrong path
Roberto.
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Re: PWMSlope Behavior
rimai wrote:Can you post your schematics?icecool2 wrote:Well, you can mark Recom drivers as compatible with your design. I do have some isolation built into my PCB, but nothing unusual that you wouldn't expect any novice to design in.
I'm interested to know how you connected the RA GND to your drivers.
I'm starting to think I originally led nanotrevor into the wrong path
Re: PWMSlope Behavior
Sorry Trevor...
I've been reading lots of places that people just have these problems with the buckpucks. Not just you.
The solution always seems to be optoisolation, like we've been working on.
But, there was a couple of places where they mention connecting the Vin- to ground, instead of LED- to ground.
I don't know if that would make any difference on the whole issue, but it would be worth trying.
I've been reading lots of places that people just have these problems with the buckpucks. Not just you.
The solution always seems to be optoisolation, like we've been working on.
But, there was a couple of places where they mention connecting the Vin- to ground, instead of LED- to ground.
I don't know if that would make any difference on the whole issue, but it would be worth trying.
Roberto.
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- Joined: Thu Jun 02, 2011 1:58 pm
Re: PWMSlope Behavior
i actually tried that on another arduino based controller i had tried and it didn't work connecting to vin - instead of led -rimai wrote:Sorry Trevor...
I've been reading lots of places that people just have these problems with the buckpucks. Not just you.
The solution always seems to be optoisolation, like we've been working on.
But, there was a couple of places where they mention connecting the Vin- to ground, instead of LED- to ground.
I don't know if that would make any difference on the whole issue, but it would be worth trying.
Re: PWMSlope Behavior
Sorry, I don't have a schematic handy. I have a current limiting resistor on the signal line from the RA to the driver. On the driver side, I have the digital ground separated from the analog ground and joined with a small bridge. There is also a weak pull up on the driver as well. I have the GND from the RA run to the digital ground of the drivers. The analog grounds are connected on the AC side between the RA and the power supplies for my drivers.
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Re: PWMSlope Behavior
Yikes. Sounds like problems all over.
Maybe I'll skip trying to get the Buckpucks to run off the PWM and get some RA moonlights instead.
Maybe I'll skip trying to get the Buckpucks to run off the PWM and get some RA moonlights instead.
-Ralph
DVRC's Mantis Shrimp Addict
15g display/7.5g sump - G. Chiragra & G. Viridis | 35g build in progress - future O. Scyllarus
DVRC's Mantis Shrimp Addict
15g display/7.5g sump - G. Chiragra & G. Viridis | 35g build in progress - future O. Scyllarus