Starting light working group

[Mopar 151]

I'll be posting up items relating to the new starting light system here - requests for advice, project assignments, the master BOM, and the like.

[Rabbit Farmer]

I can't do electrical, I can't weld, etc., but I can be the gopher to grab drinks and sandwiches when needed.

Really... anything I can do to help, I'm willing.

Steve

[jkale]

Welder?..oh wait... Brainstorm some ideas?

[sonicyellow]

I've got some duct tape...

But really, I'm in for helping however I can. I can photograph the process...? Between getting coffees...

[Number_5]

John,
You mentioned a PLC. Do you plan to let the PLC do the timing and send the results to the computer. Do you have a PLC picked out yet?
John M

[KevinGale]

John,
You mentioned a PLC. Do you plan to let the PLC do the timing and send the results to the computer. Do you have a PLC picked out yet?
John M

The PLC will handle the count down logic and turning on the red light if the light beam is tripped before the green light comes on. The PLC output for the green light will also trigger the tone generator which will send the tone up the wire. The other option is to do it with an old laptop. I could write code to do that. The PLC will be more industrial strength.

[KevinGale]

I expect to have to modify the finish hardware to include the DTMF tone receiver that I already have. I can probably help programming the PLC. I've never done anything with ladder logic but I doubt it's harder than lots of other languages I've learned over the years.

[Mopar 151]

John,
You mentioned a PLC. Do you plan to let the PLC do the timing and send the results to the computer. Do you have a PLC picked out yet?
John M

for little more, this gizmo #6884K2 will almost certainly handle start functions. it would need a small inverter for power
Need to program a PLC but don't know how? Not a problem for this user-friendly PLC—it'll lead you through step-by-step with plain-English text screens as you program and execute up to six simultaneous programs. With a 32KB memory capacity and EEPROM backup memory, this PLC retains all programming during power outages. Use to program automation jobs and as a replacement for relays, timing relays, and time switches.
Controllers have six 12-14 VDC inputs and four relay outputs (10 I/O) rated 5 amps @ 115 VAC. Processing speed is 1000 lines/1 second. They include a 2-ft. power cord with a standard two-prong plug or you can hardwire directly to a 115 VAC supply. Both are DIN-rail or panel mountable (have two 0.138" dia. mounting holes, hardware not included). Both have screw-terminal connections. Run on 115 VAC.
Controller with hand-held programmer includes a 1-ft. long connection cable.
Controller with PC software includes a serial interface cable and software. You'll need a PC running Windows 95 or better with a CD-ROM drive and an RS-232 serial port.

[Rabbit Farmer]

Just trying to understand this to keep involved.

DTMF = Dual-tone-multi-frequency

DTMF (dual tone multi frequency) is the signal to the phone company that you generate when you press an ordinary telephone's touch keys. In the United States and perhaps elsewhere, it's known as "Touchtone" phone (formerly a registered trademark of AT&T). DTMF has generally replaced loop disconnect ("pulse") dialling. With DTMF, each key you press on your phone generates two tones of specific frequencies. So that a voice can't imitate the tones, one tone is generated from a high-frequency group of tones and the other from a low frequency group.

PLC = Program Logic Controllers

Steve

[KevinGale]

We believe that DTMF will be a good choice because any normal noise is unlikely to trip the receiver. It works for the phone system and we are basically a very local phone system.