switching a relay

[ivanhoew]

just a quick question ,

i'm trying to use the mj to switch on a solenoid that will bypass propane at a set rpm and boost level ,

if i connect a relay switch wire to a switched to earth terminal on mjlt,set at 3200rpm , ,and then the pos wire of the relay switch to the next switched terminal set to 1.2bar ,but set to inverse ,will that then switch the relay ?

also ,i hunted high and low but i cant find the diagram that tells me which terminals on the mj are which switched inputs/outputs , on v 3 .lots of info on v4 ! but not on v3 .i have probably missed something obvious.

thanks ,
robert.

[brentp]

Hi Ivan,

This should help:
http://www.autosportlabs.net/MJLJ_V3_ve ... hift_Light

[ivanhoew]

Hi Ivan,

This should help:
http://www.autosportlabs.net/MJLJ_V3_ve ... hift_Light

thank you brent ,thats very handy .

i could not see any reference to the inverse part of the switching setup page , have i got it right in my first post ?

thanks
robert.

[trevil]

I think invert means that it will give negative below the value set, or else it will give negative above. Or at least I mean I saw that somewhere..

But to answer your question, no, it will not work.

[alexander]

just a quick question ,

i'm trying to use the mj to switch on a solenoid that will bypass propane at a set rpm and boost level ,

if i connect a relay switch wire to a switched to earth terminal on mjlt,set at 3200rpm , ,and then the pos wire of the relay switch to the next switched terminal set to 1.2bar ,but set to inverse ,will that then switch the relay ?

thanks ,
robert.

robert, i take it you want to switch something OFF when both conditions are met?

you can achieve that with 2 relays wired as in the attached diagram, Figure 1. both relays are normally OFF, so there is power on their 87A pins, and either will power your device. if one condition is met, ie the Output A or B pin on the MJ is grounded, then that relay will switch ON, and cut power to its 87A pin. your device will still be powered by the other relay. if the second condition is met, and both relays are ON, then your device will not receive power at all, and swich off. basically, your device is powered if either relay is OFF.

if you want to switch something ON when both conditions are met, then use Figure 2. here, the power has to go through both relays in series, so your device will only be powered when both relays are ON at the same time. ie both Output pins on the MJ are grounded due to reaching the condition.

if anyone sees any flaws in my thinking, dont hesitate to correct me!!

cheers.

PS oh bugger, dont you hate that?! just realised the OPs question was 6 months ago, but will leave here just in case this is of use to anyone else.

[ivanhoew]

not at all alexander thats v helpfull .
what i want to do is open a lpg valve on my engine when above atmos,just into boost ,and when above 3k rpm and switch off above 4.5k rpm.