Can this be reversed and still work ?
Printed From: the12volt.com
Forum Name: Relays
Forum Discription: Relay Diagrams, SPDT Relays, SPST Relays, DPDT Relays, Latching Relays, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=56701
Printed Date: April 27, 2024 at 10:46 AM
Topic: Can this be reversed and still work ?
Posted By: Dan M C
Subject: Can this be reversed and still work ?
Date Posted: May 30, 2005 at 8:07 PM
Hi to all,regarding relays i have this question;can this be hooked like this and still work ?
SPDT Type:
30- to whatever needs to be turned ON
86- Ground
87- constant +12V
85- INPUT for the remote turn-ON,
so basicaly instead of 85 beeing ground it's 86,can they be reversed and still have them work ?,this is for amps use.
Thank you
Dan
Replies:
Posted By: KarTuneMan
Date Posted: May 30, 2005 at 8:41 PM
85, and 86, are reversable....as are 30 and 87
-------------
Posted By: Ween
Date Posted: May 30, 2005 at 9:33 PM
hi, should be applicable in most cases, except for relays that have a suppression diode wired internally accross the coil. just my two cents. mark
Posted By: ff-mike
Date Posted: June 01, 2005 at 10:50 AM
Ween is correct, and we should make it a habit to wire things as if the internal diode is there because it will save labor later if the relay is replaced with one that has the internal diode, or if you ever have to rewire crappy OEM wiring.
30 & 87 are reversible, but we should follow the conventions that 30 is source and 87 load for simple circuits because of less labor when adding on to the system using either a 2nd 87 output or an 87a
Posted By: Dan M C
Date Posted: June 01, 2005 at 7:52 PM
Thank you guys,i apreciate it.
Dan
Posted By: Montrealler
Date Posted: June 13, 2005 at 3:59 PM
ff-mike wrote:
Ween is correct, and we should make it a habit to wire things as if the internal diode is there because it will save labor later if the relay is replaced with one that has the internal diode, or if you ever have to rewire crappy OEM wiring.
30 & 87 are reversible, but we should follow the conventions that 30 is source and 87 load for simple circuits because of less labor when adding on to the system using either a 2nd 87 output or an 87a
Up to me it is always better to put the source on 87 and the feed on 30 that way if your source is 12 volt you will not cause a short on pin 87a when the relay is not actuated.
Posted By: ff-mike
Date Posted: June 13, 2005 at 4:15 PM
you lost me there
Posted By: Theshadow27
Date Posted: June 15, 2005 at 2:27 PM
except that the point of a relay is to act as a switch - you cant switch backwords... so you should stick with 30 as source. this goes all the way back to the original key switches where 30 was common and 87 was switched to the starter motor. autos are common ground systems so we have to keep 30 as +12.
-------------
Posted By: ff-mike
Date Posted: June 23, 2005 at 10:10 AM
Mechanical switches are reversible, electronic switches may or may not be reversible
If #30 is common, and common is ground, then all you can do with a switch is ground a circuit.
Maybe thats why DIN defined 87 as switch input, 87a as the NC ouput, and 87b as the NO output
Posted By: maglin
Date Posted: July 07, 2005 at 10:17 PM
NC - Normally Closed
NO - Normally Open
those abbriviations killed me for the longest time. lol. just to make sure the readers hear know what they mean.
|