Hmm, I don't know what you mean, like braking in a car? If so, no. All it's doing is shorting two leads to turn a device on, just needs to be momentary and logic level driveable. nick@veys.com | www.veys.com/nick > -----Original Message----- > From: pic microcontroller discussion list > [mailto:PICLIST@MITVMA.MIT.EDU] On Behalf Of Raymond Choat > Sent: Thursday, August 02, 2001 11:09 AM > To: PICLIST@MITVMA.MIT.EDU > Subject: Re: [EE]: Solid state relay difficulty > > > Are you using this "relay" for braking? > > > ----- Original Message ----- > From: "Nick Veys" > To: > Sent: Thursday, August 02, 2001 7:26 AM > Subject: Re: [EE]: Solid state relay difficulty > > > > Ok, first I want to thank everyone who replied to this... The > > responses make perfect sense, I picked the wrong part. I guess the > > next time I need to switch a light bulb, I'll be ready! > > > > Here is what I am trying to do. > > > > I have a shorting block I want to control from a PIC. I picked a > > relay since it's basically able to mimic a momentary > pushbutton which > > is what I am trying to do. I assumed a "relay is a relay" so I > > thought a solid state relay would behave like any other > relay, I was > > wrong! :) > > > > So basically I need some way to short a block momentarily, > preferably > > without any additional hardware between it and the PIC > (which is why I > > picked the previous relay, had 5V input, low low amperage > to switch). > > > > Speed isn't a big issue, it needs to be able to switch > on/off within > > ~500ms. > > > > If anyone can perhaps show me the "correct" solid state > relay I would > > really appreciate it, as I don't want to just try again and > see if I > > pick a DC one this time! :) > > > > Thanks again for all the answers! > > > > nick@veys.com | www.veys.com/nick > > > > > > > -----Original Message----- > > > From: pic microcontroller discussion list > > > [mailto:PICLIST@MITVMA.MIT.EDU] On Behalf Of Ned Seith > > > Sent: Thursday, August 02, 2001 4:12 AM > > > To: PICLIST@MITVMA.MIT.EDU > > > Subject: Re: [EE]: Solid state relay difficulty > > > > > > > > > Nick, > > > > > > The phototriac is intended to switch high voltage AC > currents from a > > > low voltage DC source and to provide dielectric isolation (7,500V > > > insulation) between the DC and AC sources. As per the pin > out that > > > you provided: Pin 3 is the anode of the phototriac's > internal LED. A > > > DC current (+) of 10mA to 25 mA should be applied to pin 3 to > > > illuminate the internal LED and to turn on the triac. Pin > 4 is the > > > cathode of the phototriac's internal LED and is > frequently connected > > > to the DC power supply's common (-). Pin 1 is typically > connected to > > > the AC load. The other end of the AC load is connected > > > directly to the AC power source (excluding fuses/circuit > > > breakers). Pin 2 is connected to the AC common. A true test > > > of the triac's performance requires an AC power source, an AC > > > load and a low voltage DC power source. However, a crude > > > basic functional test may be performed using DC. While not > > > intended, nor conventional, the triac may be used for certain > > > DC applications, however, generally there are more > > > appropriate DC devices. > > > > > > Vasile, > > > > > > A triac will turn off or interrupt DC current, if the DC > current is > > > pulsed energy and decreases in amplitude to near zero > volts. As an > > > example, a triac will effectively control a half wave or > full wave > > > rectified DC signal. However, an SCR would be a more appropriate > > > control device. > > > > > > Good Luck! > > > Sincerely, > > > Ned Seith > > > Nedtronics > > > 59 3rd Street > > > Gilroy, CA 95020 > > > (408) 842-0858 > > > > > > > > > > > > > > > At 09:22 AM 8/2/01 +0300, you wrote: > > > >It seems you don't know how a thyristor or a triac works. If you > > > >supply A-K ( thyristor ) or A1-A2 ( triac ) ( A = anode, K = > > > >cathode ) in DC the AK or A1-A2 junction will stay on after > > > a gate or > > > >opto command until the currrent through this junction will > > > go to zero ( > > > >in fact must be less than sustain current) and this will > > > never hapened > > > >in DC . Use a bulb for test and supply it in AC. Will works. > > > >Cheers, Vasile > > > > > > > > > > > >On Thu, 2 Aug 2001, Nick Veys wrote: > > > > > > > > > Hi all, I'm using an Omron G3MB-202P solid state relay, > > > 5V flavor. > > > > > It's a phototriac. It's not behaving how I would > expect though, > > > > > hopefully someone can clear this up.. > > > > > > > > > > Pin definitions: > > > > > > > > > > 1 - load > > > > > 2 - load > > > > > 3 - (+) input > > > > > 4 - (-) input > > > > > > > > > > Here's what I am seeing: > > > > > > > > > > Connections: to test this I just want to light an LED... > > > > > > > > > > 5V to Anode of 5V LED > > > > > pin 1 - cathode of LED > > > > > pin 2 - ground > > > > > pin 3 - ground > > > > > pin 4 - ground > > > > > > > > > > This is how I start it up. > > > > > > > > > > Now when I apply power to this, of course nothing > happens as I > > > > > expect. I then switch over the pin 3 to +5V, the LED > lights, as > > > > > expected, I then switch the pin 3 back to ground, the led > > > stays lit. > > > > > In fact, no arrangement of the input pins (3,4) will make > > > the damn > > > > > LED shut off, I can't break the circuit once it's made... > > > Doesn't > > > > > sound too useful of a relay! > > > > > > > > > > Hopefully I'm doing something obviously wrong!! > > > > > > > > > > I've tried this with 3 different relays so I doubt they are > > > > > defective... > > > > > > > > > > Someone please smack me and tell me the simple solution! :) > > > > > > > > > > Thanks all! > > > > > > > > > > -- Nick > > > > > > > > > > nick@veys.com | www.veys.com/nick > > > > > > > > > > -- > > > > > http://www.piclist.com hint: The PICList is archived > > > three different > > > > > ways. See http://www.piclist.com/#archives for details. > > > > > > > > > > > > > > > > > >-- > > > >http://www.piclist.com hint: The PICList is archived three > > > >different ways. See http://www.piclist.com/#archives > for details. > > > > > > -- > > > http://www.piclist.com hint: The PICList is archived > three different > > > ways. See http://www.piclist.com/#archives for details. > > > > > > > > > > > > > -- > > http://www.piclist.com hint: The PICList is archived three > different > > ways. See http://www.piclist.com/#archives for details. > > > > > > > > -- > http://www.piclist.com hint: The PICList is archived three > different ways. See http://www.piclist.com/#archives for details. > > > -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.