Oh yes, had a 500w underwater light placed in a bucket of ice water for days while circuit was running, dimming from 0-100% brightness with no problem. The datasheets describes these "standard" triac with built in snubbers to handle phase control/light dimmer applications. I also have an...
Sorry for skipping right to the climax:
Load = incandescent bulb, 500W
voltage is 120VAC
triac is standard (designed for light dimmer), 8A rated, 600V
there is a snubber (0.1uF cap with 100ohmr resistor in series) across triac terminals
also there's an MOV across terminals
Gunnar,
are you saying that by pulsing the triac (opto) with a pw of 500us shouldn't kill the triac? THe load is a 500W, 120Vac incandescent bulb. SO for sure I am getting over the holding current. And I have verified on a scope looking at the triac trigger pulse width versus my zero cross...
I currently turn a triac on using an optocoupler MOC3052. I saw when writing the code that I need to pulse the MOC3052 optocoupler(from the microcontroller digital output)for a pulse width of 400-500us. I tried smaller pulse widths and couldn't get the triac to come on every zero crossing. Any...
HI All
I am using a zero cross detector chip placed at the front of my ac input connection, to detect AC voltage zero cross for phase control. I would think the RC snubber on the front end would delay the zero cross detection for every 1/2 cycle??
Maybe I could place a snubber circuit at the...
I currently have a 100 ohm and .1uF across the MT1 and MT2 terminals of the triac and currently have a flickering occurring. When I am connected to building power =no problem. WHen I am connected up to a generator that's when i get the problem. DO I know have sufficient snubber across the triac?
Conventionally I have always used a 1n4004 diode across a relay coil to prevent any back EMI. I have this solenoid application and was going to put diode across its coil. I have read previously that a fast recovery diode is recommended, rather thant the standard 1n4001-4004 series. Any thoughts...
Thanks for the replies. To start it's in existing design that I have inherited for some reason. I'm just looking for a fix in the field. If the design was preliminary (of course) standoffs would have been the obvious solution. Oh well. Thanks for the suggestions.
Hi Everyone. had a question. I have two pCbs mounted very closely to one another. I want to prevent from one board touching the other due to vibration, etc. Anyone know of any isolating material. I know I could conformal coat both boards, that might help. Maybe I could use a piece of neoprene or...
Itsmoked,
It is in a ROV. There are only three of these buggers inside a aluminum can, 10"ID x 12"L, filled with oil. In our tank the temp (in FLorida) is 80-90F, but the ROV will be stationed on a ship, with sea temps of 50-60F. oil is the best medium for transferring heat from an...
I got a basic question regarding power resistors. I know when specifying a power resistor, the power rating shall be twice the expected dissipated power. For example, I am using 3000 ohm, 10W resistor in a circuit application in which 120VAC will be across it. It is a nice power resistor from...
Itsmoked,
I am connecting an SMPS (AC-DC)to my triac circuit. There is no DC load connected. I measure the AC voltage out of my triac circuit (the AC input to the SMPS) and it reads ~120-135VAC. Now, the input to my triac circuit is 220VAC so when I digitally control my triac (not as a dimmer...
Didn't know this but now I do. SMPS require a minimal input current to operate? What I did was place a power resistor in parallel and the SMPS is working fine.
Cbarn that makes sense. The triac must see current in both directions to stay latched. I am using an opto-triac (MOC3052) to fire the 3 terminal Teccor triac. I would think there's a work around to use a triac to power up a SMPS. Could implement so some of filter on the front end o the SMPS...
