Buy Yamaha Outboard Parts


No announcement yet.

99yam ?

  • Filter
  • Time
  • Show
Clear All
new posts

  • 99yam ?

    Do you have a peak reading volt meter or an adaptor?

  • #2
    I made an adapter and then checked it against a peak reading meter I borrowed from a friend that use to be in the Marine business


    • #3
      Could I trouble you to get you to take a reading of something on your motor in both regular AC volts and then in peak DC volts?


      • #4
        what would you want a reading on?
        lighting or charge coil maybe?

        how soon?
        maybe this evening so I am not standing out in the sun shine.
        need to locate the adapter, have not used it in a few years
        Last edited by 99yam40; 2 weeks ago.


        • #5
          Does not matter what you take the reading on. No rush.

          There is a formula to get from a peak voltage reading to an RMS reading. That same formula can be rearranged to get to peak from RMS. Makes me wonder why the need for a peak reading meter.


          • #6
            I know that my Fluke 87 with peak/ min/ max voltage setting did not come close to what the specs were.
            so that is why I made an adapter
            I will try to get some reading this evening after I mow the yard


            • #7
              OK I checked the charge coil loaded ( wire stuck up the bullet connectors with motor running @ 1500 RPM I read 237VDC with my adapter and on AC with just my voltmeter set to AC I read 61 - 65 VAC

              At around 3500 on DC with adapter I read 162 VDC and on just my meter set at AC, 59VAC

              I do not think this will relate to a formula if that is what you are looking for


              • #8
                What does your meter read when measuring wall outlet voltage? Thanks.


                • #9
                  121.2 VAC

                  162.7VDC with adapter


                  • #10

                    V rms = V p / the square root of 2

                    V rms = 162.7 / 1.414 = 115

                    Pretty darn close.


                    • #11
                      V p = V rms X 1.414

                      V p = 121.2 X 1.414 = 171

                      Should be close enough for government work.


                      • #12
                        what about the readings I got on the charge coil on my C40?

                        I will need to use my fluke 87 tomorrow again to see if I understand how to use it properly for peak to compare to the readings with the Adapter I made.
                        I just took readings again on an outlet here in the house and to find peak I had to push the min/Max button and then the button below it labeled peak/min/ max to get a reading of +162 for max and -162 for min.
                        Last edited by 99yam40; 1 week ago.


                        • #13
                          Puzzled over your charge coil readings.


                          • #14
                            Originally posted by boscoe99 View Post
                            Puzzled over your charge coil readings.
                            Sinusoidal AC.
                            Maybe charge coil signal is not a smooth sine wave?


                            • #15
                              I always thought the cap, diode, and resister was to build up and hold the charge voltage long enough so the meter could see it better.
                              anyway you look at it, if they set the specs minimum with using the special peak reading meter, I am not sure you can use anything else to compare to the spec voltages

                              higher RPM means a lot higher frequency as those magnets fly by the coils