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glennk
06-02-2017, 01:31 AM
Just have a quick question about fading using ssr's I've been trying to figure this out for some time now and reading the posts here I'm just getting more confused lol I'll probably just go with on off blinky lights but I did find these on Amazon and the description does say they are zero cross


https://www.amazon.com/gp/aw/d/B006J4G45G/ref=mp_s_a_1_12?ie=UTF8&qid=1496380884&sr=8-12&pi=AC_SX236_SY340_FMwebp_QL65&keywords=solid+state+relay
Just wondering if these will work

Callender
06-02-2017, 06:12 AM
Those SSR boards will not be fade able. I have them and they do not allow fading. Also the price on Amazon is about twice of what you can find on eBay for equivalent boards. The reason that they don't fade is pretty technical and others can explain it better than me. If you what fading, then look at Renard boards like the SS16. They look more expensive but they are the best option to fade ac lights.

ukewarrior
06-02-2017, 10:19 AM
IN order to fade AC light strings, you have to have the ability to detect 'zero cross' which is the point where the AC wave crosses over the 0 volt reference as it ALTERNATES 'up and down'.
Very different than DC strings and pixels.

All Renards that drive AC strings do this as well as their sometimes used daughterboards, the SSRs like the SSR neon and SSRez, etc...

glennk
06-02-2017, 12:24 PM
That's what I thought so I'm just going to do the blinky light thing for this year and work on new controllers for next might get those though cause I'm getting tired of hearing castanets playing in the background (using mechanical relays ATM) thanks for the info

ukewarrior
06-02-2017, 04:37 PM
Any chance you are coming to LUO tomorrow in Columbus?!!?
Lots of folks can talk about this in detail.

That's what I thought so I'm just going to do the blinky light thing for this year and work on new controllers for next might get those though cause I'm getting tired of hearing castanets playing in the background (using mechanical relays ATM) thanks for the info

MartinMueller2003
06-02-2017, 05:21 PM
Actually, your SSR must NOT have the zero cross feature. If the SSR itself has the ZC feature then you can only trigger it near the ZC time, making it full on only. Controllers like the Renards have a ZC detection circuit so that they can send an ON signal to the SSR part way through the AC cycle. That is how they achieve dimming (later in the cycle means less energy means less light).

ukewarrior
06-02-2017, 06:17 PM
Correct.
I wasn't clear that you use the SSRs with controllers like the REN64, which need the SSRs, but the actual zero cross is in the REN controller.

Actually, your SSR must NOT have the zero cross feature. If the SSR itself has the ZC feature then you can only trigger it near the ZC time, making it full on only. Controllers like the Renards have a ZC detection circuit so that they can send an ON signal to the SSR part way through the AC cycle. That is how they achieve dimming (later in the cycle means less energy means less light).

BF210
06-02-2017, 11:58 PM
I'll take a stab at the technical, just for completeness. I'm sure the wiki has good detail if you need more info. The term "zero crossing" or zero-cross (sometimes ZC) has two meanings but both refer to the same event: the point where the continuously-changing AC voltage passes through zero on its way from positive to negative or negative to positive. The zero crossing is used both as a timing reference for dimming circuitry and as a safe time to switch certain loads on or off with minimal electrical noise.

A solid state relay (SSR) for dimming must be able to turn on at any point in the AC cycle so the load only receives a percentage of the current. An SSR with a ZC function includes additional circuitry that delays turning it on until the next zero-crossing event. This ensures pure on/off operation with loads that do not support dimming (cheaper fluorescent lights) or speed control (many motors.)

Rodney D
06-03-2017, 06:10 PM
BF210 Is correct. If you were going to look for SSR's or boards that would allow dimming of AC Must be NON Zero Cross SSR's.
Mechanical Relays will not work at all for fading and contacts will wear quickly even in simple On/Off show applications.
I think what you will find "like I did" is your options are limited to:
1. build your own board with NON Zero Cross SSR's.
2. buy pre-made like the Renard Board
3. Change to DC powered lights "opens more possibilities for fading control"
4 Simply use the Relay board you found on Amazon as a simple On/Off show.
Good Luck.