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soakes94
07-16-2010, 03:12 PM
Ive built some DC SSR's and connected them to my grinch controlled by a ren-c, i have both cables running between the ren-c and the grinch and both have a power supply. The lights are 12v led's and dim up and down fine however when I measured the voltage of the leds it was only 6v. Ive checked everything and cant seem to find any problem anywhere. Can anyone help?

Thanks in advance Stephen

LabRat
07-16-2010, 03:17 PM
Ive built some DC SSR's and connected them to my grinch controlled by a ren-c, i have both cables running between the ren-c and the grinch and both have a power supply. The lights are 12v led's and dim up and down fine however when I measured the voltage of the leds it was only 6v. Ive checked everything and cant seem to find any problem anywhere. Can anyone help?

Thanks in advance Stephen

Where were you measuring?
Did you try between +V and GND at the DCSSR itself?

soakes94
07-16-2010, 06:53 PM
I measureed the voltage at the output, the input voltage for t led meausres 12v but the output is only 6v

budude
07-16-2010, 07:41 PM
Remove the LED from the output and measure from the +DC to the output pin and verify if you are seeing 12v there or not with the channel on. Remember these are switched grounds. If that's OK then you know the SSR is working OK.

Can you describe exactly how you have things wired up? Where is the current limiting resistor installed in the path and what do you see across that?

I'm a little confused because you indicated it dimmed up and down fine?

soakes94
07-17-2010, 07:08 AM
Ive attached a picture of my DC SSR, the resistors between the opto and input are 680 ohm, the resistor on the 12v is a 10k ohm and the resistor between the opto and the mosfet is a 470 ohm. The 2 screw terminals read 12v, when I activate the channel to 100% im only getting about 6v out. I take this reading by keeping the positive end of the tester on the 12v screw terminal at the top and place the negative on the output screw terminal.

Can anyone help?

LabRat
07-17-2010, 11:12 AM
What are you using to trigger the DCSSR? Any chance it's doing a PWM at about 50%? (Just looking to rule out the silly .. but sometimes overlooked solutions)

How about a picture of the underside, so we can double check the circuit?

budude
07-17-2010, 11:31 AM
It appears you etched your own boards - good for you! Can you list exactly which parts you used for the MOSFET and opto? Just wondering if the FET is not turning on completely or something...

soakes94
07-17-2010, 11:40 AM
Ive set it to 100% and my output is still 6v, Ive attached a picture of the bottom hope it helps

Thanks for all your help

soakes94
07-17-2010, 11:51 AM
Ive used 78L05 for my voltage reg, ive got 680ohm resistors between the opto and input, ive got a 10k ohm on the 12v into the mosfet, and a 470 ohm between the opto and mosfet and im using a RFD14N05L for the mosfet and also a 100nF cap.

thanks stephen

soakes94
07-17-2010, 11:58 AM
Oh and the opto is a k847p

LabRat
07-17-2010, 12:34 PM
Same voltage reading on all four outputs?

What if you don't use the REN-C? (I'm assuming the REN-C F/W wouldn't know that you have DCSSR's attached, so it's output may not be just "ON".. and then later .. "OFF")

Have you got an SSR tester, that you could just close a switch to turn the SSR on? As you are home etching there are a couple of samples in the FILES section. It might help. (The testers usually double as a cable tester as well, so it's a reasonable investment of time to make one)

christmas-light
07-17-2010, 12:58 PM
I am just asking here: The Firmware on the Ren-C, do you not have to set it up to controll DC and not AC ?

soakes94
07-17-2010, 01:05 PM
I dont have one so I will make one and get back to you on the results, I took a volt meter and had a look at the input voltages from the grinch which is controlled by the ren-c and I got 2.30 volts, I dont know if this is normal for the ren-c or if it should be 5v like the grinch outputted.

Thanks Stephen

soakes94
07-17-2010, 01:11 PM
I'm not sure what software is on the pic, its just what wjohn sent me

dirknerkle
07-17-2010, 02:42 PM
I am just asking here: The Firmware on the Ren-C, do you not have to set it up to controll DC and not AC ?

The Ren-C only works with a Grinch or 595 board and does not have any capability for DC or AC. The Ren-C is a translator, of sorts, that translates a serial signal into a format that the Grinch/595 can understand, which normally are connected to the parallel port.

christmas-light
07-17-2010, 02:47 PM
The Ren-C only works with a Grinch or 595 board and does not have any capability for DC or AC. The Ren-C is a translator, of sorts, that translates a serial signal into a format that the Grinch/595 can understand, which normally are connected to the parallel port.

Yes, I know what the Ren-c does, (learned for the wiki ;) ), but I was just wondering, because on a eg. Ren 64 you have to do that :o

jmksparks
07-17-2010, 05:43 PM
Is the program in the ren,c set for 60hz because soakes needs 50hz for the UK. ? would that be the cause.

soakes94
07-17-2010, 05:51 PM
It works ok with mains lighting, however there is a flicker but that could be the hardware in the switch

jmksparks
07-17-2010, 05:57 PM
That would have been my other question, thats good. Back to the drawing board!.

budude
07-17-2010, 05:59 PM
Is the program in the ren,c set for 60hz because soakes needs 50hz for the UK. ? would that be the cause.

The Ren-C code is self-adjusting for 50/60Hz. Also DCSSRs work on active low signals as the ACSSRs do so you do not need to invert the signal out. You only need to change it when using inverting drivers such as ULN2803s or transistors. AFAIK there are no changes to the code required for Ren-C's but Phil could confirm this...

jmksparks
07-17-2010, 06:20 PM
Thought that was the case although I seem to remember some talk about 50hz issue.

jmksparks
07-17-2010, 07:23 PM
Anybody noticed that his mosfet has a zener internal as opposed to the norm of diode based, ! That is the extent of my observation

ctmal
07-17-2010, 09:11 PM
I am by no means an expert but are the mosfets source and drain backwards? Also, I can't tell where the 10k resistors are going. I think they should be going between the gate and 0v.

I'm looking at the DCSSR schematic (http://www.doityourselfchristmas.com/wiki/images/0/09/DCSSR_Sch_1.1.pdf) as a reference.

Somebody with more experience please chime in on this.

edit: I looked again and it does look like the 10k resistors are going between the gate and 0v.

LabRat
07-17-2010, 10:10 PM
The Ren-C only works with a Grinch or 595 board and does not have any capability for DC or AC. The Ren-C is a translator, of sorts, that translates a serial signal into a format that the Grinch/595 can understand, which normally are connected to the parallel port.

Hang on.. something seems amiss with my understanding here.

Grinch - on/off only.. it has no idea about dimming because it has no ZC capability.
- interfaced via "clocked" in data to a latch, which controls each port.
REN-C - serial interface (does serial to clocked/latch data conversion)
- provides "DIMMING" via ZC signal passed in to it.

So if we have a version of the RENARD that is custom compiled for PWM output (when talking to DCSSRs), shouldn't such a firmware exist for the REN-C?

I'm open to be educated here. But I have to wonder, if the lack of a ZC signal couldn't result in the output being "off" for 1/2 of the duty cycle.
Manifesting as an appearance of 1/2 the voltage.

Hey.. it's just a theory.

So this REN-C... does it have a ZC signal coming into it?

jmksparks
07-18-2010, 12:07 AM
Hang on.. something seems amiss with my understanding here.

Grinch - on/off only.. it has no idea about dimming because it has no ZC capability.
- interfaced via "clocked" in data to a latch, which controls each port.
REN-C - serial interface (does serial to clocked/latch data conversion)
- provides "DIMMING" via ZC signal passed in to it.

So if we have a version of the RENARD that is custom compiled for PWM output (when talking to DCSSRs), shouldn't such a firmware exist for the REN-C?

I'm open to be educated here. But I have to wonder, if the lack of a ZC signal couldn't result in the output being "off" for 1/2 of the duty cycle.
Manifesting as an appearance of 1/2 the voltage.

Hey.. it's just a theory.

So this REN-C... does it have a ZC signal coming into it?

He does say that it works for AC, I presume he means that his 240v ssr,s work with a flicker. He is most likely asleep now so will have to wait.

soakes94
07-18-2010, 06:05 AM
I can control 240v ac lights and dim them which is great there is just a small flicker though. Can someone tell me what output I should be getting from the grinch as I'm getting about 2.3v at full power and I thought it would of been 5v, but I'm not sure.

Thanks for all your help :)

LabRat
07-18-2010, 06:17 AM
I don't use a GRINCH thus I'm very much thinking of this theoretically. But it would seem that you measurement at the GRINCH is about 1/2 expected, so again I'm theorizing that your signal is actually "ON" for only 1/2 of the time. This would appear to your standard voltmeter as about 1/2 the voltage.

What are you using for your Zero Cross detection circuit? I can see in the wiki that the REN-C relies on having this signal passed to it (often from a REN-T).

Any chance you would have access to a scope, or a logic probe? If you have a PicKit2 it can be made to operate as a basic logic analyzer, and you could easily measure/watch the signal on the Grinch itself to see if it is on 100%, or if it is actually cycling on/off with a 50% duty cycle.

ps. I'm off on Holidays.. so may not be able to see the outcome of this. I *do* hope you manage to track this down soon. Best of luck... cheers.

soakes94
07-18-2010, 11:26 AM
Im using a H11A1 and a 24v ac power source with the 3.3K ohm resistor on both inputs. I sadly don't have a scope or anything else like that, im 16 and new to all of this so I don't have any major equipment yet. I took a reading from all the test points on the ren-c and got these results:
Test Point 1: 4.41v
Test Point 2: 0.02v
Test Point 3: 0.02v
Test Point 4: 3.82v
Test Point 5: 0.02v

Ive got no idea what is happening, I can only think its a problem with the ren-c, but it works with AC so im not sure

Thanks everyone that has helped me with this already, I hope you guys can come up with a fix as I've got no idea what im doing

soakes94
07-18-2010, 12:00 PM
Just took a reading of my 240v ac lights and Im only getting about 127v on that, so this seems to be a bigger problem than first though and I took a reading for a set of 24v ac Christmas lights and I got a 15.1v output. So its not my SSRs i dont think but either the grinch or ren-c output, as im only getting about 2.3v input to the SSR from the grinch.

Does anyone have any ideas now that its a problem over all of my SSRs? or has this made it worse?

budude
07-18-2010, 12:17 PM
You mentioned you are using the H11A1 chip to generate ZC? I seem to recall you need the H11AA1 as the H11A1 only generates ZC for the half cycle where the H11AA1 does both. I'll try and find the post but I think the Wiki entry for the Ren-C ZC input was wrong and should point to the H11AA1...

Edit - yep - check this out - http://doityourselfchristmas.com/forums/showthread.php?t=8954&highlight=H11A1

soakes94
07-18-2010, 12:31 PM
So if I swap the IC's in the ZC could that solve my problem?

budude
07-18-2010, 01:02 PM
So if I swap the IC's in the ZC could that solve my problem?

Yes - either that or there is a post in there about adding diodes as well. I'm pretty sure this will fix your issue though.

jmksparks
07-18-2010, 01:15 PM
Well spotted sir, and as far as the flickering I used screened cable from my xc to the Ren,s, ( the screen being grounded ) all I am left with now is a very minor flick on the last channel of each of the four homemade Olsons. Can live with that.

soakes94
07-18-2010, 06:17 PM
Ive ordered the new part and it should be here on Tuesday I'm hoping, I will let you guys knows the results :)

thanks for all your help :)

LabRat
07-18-2010, 08:56 PM
Oh man.. I was going to post this as an option (as I had made the same mistake) but was waiting to hear about your ZC solution. This is good news as it's such an easy fix.

soakes94
07-20-2010, 05:01 PM
Woooo! new part came today :) I put it and it works i have the biggest smile ever :p thanks so much everyone, im so pleased :) woo :)

budude
07-20-2010, 05:06 PM
Good to hear - happy blinky-flashy!