Testing Hall Sensor
12-09-2010 | 11:57 PM
#3
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From: Lancaster,
NY
RE: Testing Hall Sensor
You could pull the spark plug, hook up your voltmeter (ground to case, positive to signal output of sensor) then spin the motorwith your starter and seeif you see a readable voltage. At a fast enough rpm the spikes will look like a constant voltage.
12-10-2010 | 12:12 AM
#4
RE: Testing Hall Sensor
That's not how a hall sensor works, it doesn't generate voltage. It acts merely as a switch, opening and closing a circuit as the magnet passes. There is actually a dozen or so components inside the little chip that is a hall sensor on a Rcexl or C&H ignition. I've never spent the time to figure out whether one could be tested accurately with an ohm meter.
I wrote this troubleshooting guide for testing Rcexl ignitions, the sensor is tested in the process, it will work for most C&H ignitions also.
<span style="LINE-HEIGHT: 115%; FONT-FAMILY: "Verdana","sans-serif"; FONT-SIZE: 10pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA">Take an old expendable servo extension and cut off the male plug end, separate the wires, strip a bit of insulation from each of the 3 leads and plug the other end into the sensor lead on the ignition module. Put a good CM-6 plug in the cap, doesn't need to be all the way seated but far enough for the hex of the plug to make contact with the metal shell of the plug cap, plug a fully charged 4 cell battery directly into the ignition. Test for battery voltage at the red and black wires of the test extension you made and plugged into the sensor lead of the module, if there is no voltage replace the module, if there is battery voltage......Short the white and black wires together, every time you break this connection there should be a spark, no or intermittent spark=bad module, has good spark......Remove the test lead and plug the sensor on the engine into the module and turn the engine over, no spark, replace the sensor, good spark.... Remove the spark plug, look down into the plug cap and turn the engine over, if you see spark arcing through the silicone boot to the metal shell, replace the spark plug cap, no visible spark but you hear a snap.....Put a small screw driver into the bottom of the cap, turn the engine over and you should observe spark jumping from the screw driver to the plug cap shell outside of the silicone boot, an arc of about 1/4"-3/8", if it does this there is nothing wrong with the ignition, if you hear an arc but it's not in the cap with the screw driver it could be a problem with the </span><span style="LINE-HEIGHT: 115%; FONT-FAMILY: "Calibri","sans-serif"; FONT-SIZE: 11pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA; mso-ascii-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-theme-font: minor-bidi"><span style="LINE-HEIGHT: 115%; FONT-FAMILY: "Verdana","sans-serif"; COLOR: black; FONT-SIZE: 10pt; TEXT-DECORATION: none; mso-bidi-font-family: Arial; text-underline: none">resistor</span></span><span style="LINE-HEIGHT: 115%; FONT-FAMILY: "Verdana","sans-serif"; FONT-SIZE: 10pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA"> in the cap or the high tension lead where it goes into the cap, replace the plug cap.
All of this can be done on a bench, the plug does not need to be grounded to the engine.</span>
I wrote this troubleshooting guide for testing Rcexl ignitions, the sensor is tested in the process, it will work for most C&H ignitions also.
<span style="LINE-HEIGHT: 115%; FONT-FAMILY: "Verdana","sans-serif"; FONT-SIZE: 10pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA">Take an old expendable servo extension and cut off the male plug end, separate the wires, strip a bit of insulation from each of the 3 leads and plug the other end into the sensor lead on the ignition module. Put a good CM-6 plug in the cap, doesn't need to be all the way seated but far enough for the hex of the plug to make contact with the metal shell of the plug cap, plug a fully charged 4 cell battery directly into the ignition. Test for battery voltage at the red and black wires of the test extension you made and plugged into the sensor lead of the module, if there is no voltage replace the module, if there is battery voltage......Short the white and black wires together, every time you break this connection there should be a spark, no or intermittent spark=bad module, has good spark......Remove the test lead and plug the sensor on the engine into the module and turn the engine over, no spark, replace the sensor, good spark.... Remove the spark plug, look down into the plug cap and turn the engine over, if you see spark arcing through the silicone boot to the metal shell, replace the spark plug cap, no visible spark but you hear a snap.....Put a small screw driver into the bottom of the cap, turn the engine over and you should observe spark jumping from the screw driver to the plug cap shell outside of the silicone boot, an arc of about 1/4"-3/8", if it does this there is nothing wrong with the ignition, if you hear an arc but it's not in the cap with the screw driver it could be a problem with the </span><span style="LINE-HEIGHT: 115%; FONT-FAMILY: "Calibri","sans-serif"; FONT-SIZE: 11pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA; mso-ascii-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-theme-font: minor-bidi"><span style="LINE-HEIGHT: 115%; FONT-FAMILY: "Verdana","sans-serif"; COLOR: black; FONT-SIZE: 10pt; TEXT-DECORATION: none; mso-bidi-font-family: Arial; text-underline: none">resistor</span></span><span style="LINE-HEIGHT: 115%; FONT-FAMILY: "Verdana","sans-serif"; FONT-SIZE: 10pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA"> in the cap or the high tension lead where it goes into the cap, replace the plug cap.
All of this can be done on a bench, the plug does not need to be grounded to the engine.</span>
12-10-2010 | 07:14 AM
#5
Senior Member
My Feedback: (1)
RE: Testing Hall Sensor
Should be able to read 5v every time the magnet passes the sensor from the ground lead of the hall wires, but it's not a guarantee of correct function.
You can also hear the snap Jody was referencing if the ignition is arcing to ground at the outside of the cap. Basically going from the end of the wire to the metal wall inside the cap, bypassing the plug completely. Then you have the condition where you have a cracked insulator ceramic with a spark plug where the electrical arc travels down the outside of the plug and grounds to the hex base of the plug.
Or have a loosely mounted cap where the spark arcs from the wire to the top of the plug, causing intermittant firing. That generally leaves black carbon traces on the upper portion of the plug insulator. This is very common for users of plug caps used on RC Exl ignitions because the user fails to push the cap on securely.
You can also hear the snap Jody was referencing if the ignition is arcing to ground at the outside of the cap. Basically going from the end of the wire to the metal wall inside the cap, bypassing the plug completely. Then you have the condition where you have a cracked insulator ceramic with a spark plug where the electrical arc travels down the outside of the plug and grounds to the hex base of the plug.
Or have a loosely mounted cap where the spark arcs from the wire to the top of the plug, causing intermittant firing. That generally leaves black carbon traces on the upper portion of the plug insulator. This is very common for users of plug caps used on RC Exl ignitions because the user fails to push the cap on securely.
12-10-2010 | 10:16 AM
#8
RE: Testing Hall Sensor
Thanks guys, I get more compliments on that piece than anything I've ever written, feels good to be helpful.
It was also requested that I put it into Bob Pastorello's sticky for novice gas engine users so a little easier to follow version has been posted there for quick reference and easy futureaccess, I believe it's post #20.
It was also requested that I put it into Bob Pastorello's sticky for novice gas engine users so a little easier to follow version has been posted there for quick reference and easy futureaccess, I believe it's post #20.
12-10-2010 | 02:04 PM
#11
Senior Member
RE: Testing Hall Sensor
very informative on how to check out the ignition system, but i dont know what T.O.M. is talking about, i wear the pants at my house, however the wife wears the panties, guess who wins?
]
12-10-2010 | 05:24 PM
#14
RE: Testing Hall Sensor
I would count yourself ahead...if you did not sell ALL of you RC equipment to try to save a marriage of 27+ years before it happened. I could write a book on what happened in the long run. Do not let it disappoint you & ruin years of time. I lost 9 years...but now I have someone who Loves me for who I am. Amen!
12-10-2010 | 08:06 PM
#16
My Feedback: (6)
RE: Testing Hall Sensor
No. We were together 8 years... 6 of them great. Really hurt when we split up a year and a half ago, but I'm getting over it and it didn't really cost me any money. The sad thing is I now have a beautiful 5 year old daughter with a broken home. But, she loves to spend time with "daddy", and loves airplanes, so that's way cool. I'll be alright...
Maybe I'll make it my "New Year's resolution" to take her pic off my Avatar finally....
AV8TOR
Maybe I'll make it my "New Year's resolution" to take her pic off my Avatar finally....
AV8TOR
12-10-2010 | 11:34 PM
#17
Senior Member
RE: Testing Hall Sensor
ORIGINAL: jedijody
That's not how a hall sensor works, it doesn't generate voltage. It acts merely as a switch, opening and closing a circuit as the magnet passes. There is actually a dozen or so components inside the little chip that is a hall sensor on a Rcexl or C&H ignition. I've never spent the time to figure out whether one could be tested accurately with an ohm meter.
I wrote this troubleshooting guide for testing Rcexl ignitions, the sensor is tested in the process, it will work for most C&H ignitions also.
<span style=''LINE-HEIGHT: 115%; FONT-FAMILY: ''Verdana'',''sans-serif''; FONT-SIZE: 10pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA''>Take an old expendable servo extension and cut off the male plug end, separate the wires, strip a bit of insulation from each of the 3 leads and plug the other end into the sensor lead on the ignition module. Put a good CM-6 plug in the cap, doesn't need to be all the way seated but far enough for the hex of the plug to make contact with the metal shell of the plug cap, plug a fully charged 4 cell battery directly into the ignition. Test for battery voltage at the red and black wires of the test extension you made and plugged into the sensor lead of the module, if there is no voltage replace the module, if there is battery voltage......Short the white and black wires together, every time you break this connection there should be a spark, no or intermittent spark=bad module, has good spark......Remove the test lead and plug the sensor on the engine into the module and turn the engine over, no spark, replace the sensor, good spark.... Remove the spark plug, look down into the plug cap and turn the engine over, if you see spark arcing through the silicone boot to the metal shell, replace the spark plug cap, no visible spark but you hear a snap.....Put a small screw driver into the bottom of the cap, turn the engine over and you should observe spark jumping from the screw driver to the plug cap shell outside of the silicone boot, an arc of about 1/4''-3/8'', if it does this there is nothing wrong with the ignition, if you hear an arc but it's not in the cap with the screw driver it could be a problem with the </span><span style=''LINE-HEIGHT: 115%; FONT-FAMILY: ''Calibri'',''sans-serif''; FONT-SIZE: 11pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA; mso-ascii-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-theme-font: minor-bidi''>http://<span style=''LINE-HEIGHT: 11...esistor</span></span><span style=''LINE-HEIGHT: 115%; FONT-FAMILY: ''Verdana'',''sans-serif''; FONT-SIZE: 10pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA''> in the cap or the high tension lead where it goes into the cap, replace the plug cap.
All of this can be done on a bench, the plug does not need to be grounded to the engine.</span>
That's not how a hall sensor works, it doesn't generate voltage. It acts merely as a switch, opening and closing a circuit as the magnet passes. There is actually a dozen or so components inside the little chip that is a hall sensor on a Rcexl or C&H ignition. I've never spent the time to figure out whether one could be tested accurately with an ohm meter.
I wrote this troubleshooting guide for testing Rcexl ignitions, the sensor is tested in the process, it will work for most C&H ignitions also.
<span style=''LINE-HEIGHT: 115%; FONT-FAMILY: ''Verdana'',''sans-serif''; FONT-SIZE: 10pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA''>Take an old expendable servo extension and cut off the male plug end, separate the wires, strip a bit of insulation from each of the 3 leads and plug the other end into the sensor lead on the ignition module. Put a good CM-6 plug in the cap, doesn't need to be all the way seated but far enough for the hex of the plug to make contact with the metal shell of the plug cap, plug a fully charged 4 cell battery directly into the ignition. Test for battery voltage at the red and black wires of the test extension you made and plugged into the sensor lead of the module, if there is no voltage replace the module, if there is battery voltage......Short the white and black wires together, every time you break this connection there should be a spark, no or intermittent spark=bad module, has good spark......Remove the test lead and plug the sensor on the engine into the module and turn the engine over, no spark, replace the sensor, good spark.... Remove the spark plug, look down into the plug cap and turn the engine over, if you see spark arcing through the silicone boot to the metal shell, replace the spark plug cap, no visible spark but you hear a snap.....Put a small screw driver into the bottom of the cap, turn the engine over and you should observe spark jumping from the screw driver to the plug cap shell outside of the silicone boot, an arc of about 1/4''-3/8'', if it does this there is nothing wrong with the ignition, if you hear an arc but it's not in the cap with the screw driver it could be a problem with the </span><span style=''LINE-HEIGHT: 115%; FONT-FAMILY: ''Calibri'',''sans-serif''; FONT-SIZE: 11pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA; mso-ascii-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-theme-font: minor-bidi''>http://<span style=''LINE-HEIGHT: 11...esistor</span></span><span style=''LINE-HEIGHT: 115%; FONT-FAMILY: ''Verdana'',''sans-serif''; FONT-SIZE: 10pt; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA''> in the cap or the high tension lead where it goes into the cap, replace the plug cap.
All of this can be done on a bench, the plug does not need to be grounded to the engine.</span>
Grumpy no Two.
BC
