So I got 2 summit rpm switches for operating my VDI/aux ports. The air pump I am using pulls about 4 amps and the rpm switch is only rated to 2 amps so I got a relay.
Now here is my problem: the rpm switch puts out a ground to trigger the device but the relay needs a 12V switched source to know when to trigger on. I know people have used this before, so how did you get around this? Preferably it would be using devices that one can obtain on the weekend since I want to get this done tomorrow.
Thank you in advance.

 

ground trigger from the rpm switch to pin 85 of the aftermarket relay,

12volts on 86 and 87 of the relay

30 of the relay is the positive trigger to the pump

 

Yeah I already though of that, but wouldn't the current still be going through the RPM switch since it is the only ground to the relay?
I'll go test it out real quick and check to make sure.
Edit: well hot damn, that does work. I guess I should have tested it out with the meter first. Anyway, thanks for telling me to try it Icemark!

 

The current only flows to ground when the RPM switch is activated

 

Well, the problem was that I thought it would pull the whole 4 amps through the ground wire. What actually happened was that it only pulled the 180 mA for the relay through the ground wire, so it works fine.

Now I have a new problem, though. Even when I set it on 2k rpm as the trigger, it doesn't activate until over 5k rpms. I hooked it up to the yellow/blue wire on the trailing coil since thats where aaron said to put it on a thread I found. Is this not right, or it just just not possible to get it to trigger lower than that?

 

180mA from a relay coil is pretty high... should be closer to less than 50mA

and as I recall when I last used one I had to crank the settings to a lowest possible to get a 5200 RPM trigger

 

Well, the listed nominal current is 160 mA, so its close enough. Its a monster 30A automotive relay, which could be why it pulls so much. I just got it because its what I found at radio shack on short notice.

Also, what do people do for activating the aux ports if the lowest it will go is 5200?

 

be carefull with the summit switches. Atleast the one I used, ramped up the voltage to the 12v 30a relay I was using for the aux ports and kept making it stick. I always had to open up the relay and fix it. If I hooked a multimeter up to the switch, you could see the volts climb from 0v-12v as it came close to the triggered RPM.

After I switched to a MSD and never had a problem.

wher the DIP switches are, flip the one for 3000 and the one for 800 or 600, if you are using it for AUX. Look directly across the board (if they havn't changed the design) and you will see a rotary dial that says "Adjust" printed on the board. Turn that to fine tune the RPM set point. I noticed the dip switch for 9000 was also flipped when looking at my switch that I took out of my tool chest. I don't know if I did that or if it flipped by its self from getting bumped around for years. Don't see a reason why I would have flipped both, 3000 and 9000.

Like I said above, be aware that your switch may also ramp up the voltage.

 

This is just a temporary solution. I am going to make my own RPM switch from scratch but I don't have the time or money to do it at the moment. The one I make will be fully programmable allowing for a hysteresis to avoid fluttering and to allow for a more optimal operation of the air pump.
There are directions on the globalvicinity.com vdi activation page.

 

I plug my RPM switch in the Green plug buy the coil, Its a rounded shaped female connector. Switch activates at 3800 rpm after adjusting it. Lemme know if you need pics, I can probably takes some fior ya sideways!!

 

Which coil? I see an unused female bullet connector on the leading coil. Is that what you are talking about? I can't tell the color due to age. And yes, pics would be great.
Also, I assume that you got it to work with the summit switch, right? If so, what rpm setting did you use?

 

For the record, the connectors on both the leading and trailing coils DO send out the same signal. The way to get it to trigger lower is to turn the adjustment screw almost all the way counter-clockwise. I would have tried it earlier except I though it was for fine adjustments, not huge adjustments.

 

Batteries died in the camera so I cant load them in my computer, I will try tomorrow!!

Sorry
Chris

 

Don't worry about it, I think I found the connector you were talking about. Anyway, I figure out how to get it working. In fact its actually opening a bit early right now so I gotta go adjust it to the proper RPM.

 

Ya I didn't have to adjust it that much. I suppose you could set it for 2800 and see what happends. Maybe the adjustment would be closer to the actual RPM set point.

 

You can adjust it to where it actually triggers at the correct RPM. You just have to turn the orange adjust potentiometer on the circuit board. You turn it counter-clockwise to get it to trigger at the correct rpm.

 

Sorry about that man(I did take those pics though) but yea thats how I adjusted it to 3800 using a potentiometer!! BTW the green plug was used for the power to the rpm switch. Its the white bullet female connector that I used for the RPM signal.

Chris

 

Been there, done that a few years ago on this thread: https://www.rx7club.com/forum/showth...ghlight=SUMMIT

See HAILERS about three quarters down the first page of it.

 

I wonder how I missed that. Oh wait, its because the title was "will someone help me with this thing"
Seriously, I hate it when people have titles like that.

 

Yup, that's the worst. Want to start an RPM switch article in the GV modification manual so that doesn't happen again?

Instructions: http://howto.globalvicinity.com/gv_w...i=38&co=1&vi=1

 

^ Not an RPM switch Article, An article about configuring the Summit RPM switch.

I used to have pictures of mine. I don't know what happen to them. Im probubly going to sell mine for $5 on ebay. Since I think they are only worth that much

 

The Summit Racing RPM switch is calibrated for 8 cylinder engines.

Good Luck. I have mine running off relays.

 

Indeed! Up to the challenge, Sideways? I'm imagining a configuration procedure with photos, then once it's up, others can update it with pros/cons.

 

Atleast thats what we want others to do. Hasn't happend yet

 

Certainly. I was actually planning on contacting you about doing just that. You can PM me with details about what to do.

BTW, the RPM switch I was talking about making is basically the one on your site, Steve. I'm gonna have to take the time to really look at it, but I Think I can modify the code to do what I want.
The inherent problem with this is that the air pump can't run forever. I have seen it said that it overheats and shuts down until it cools off after around 4 minutes of continuous use. While not usually over 3800 for that long, I have done it on occasion. The cool thing about this pump is that it is designed to hold in air pressure since it is used to control the size of an air bladder. Without going into detail, there is a way to run the pump for a few seconds to open the VDI/aux ports then turn off the pump but keep the air pressure locked in, then let the air pressure out once below the set rpm. Now all I have to do is to figure out a way to control it the way I want too. I have some ideas, but I haven't had the time to pursue them lately due to work loads.