element14 Community
element14 Community
    Register Log In
  • Site
  • Search
  • Log In Register
  • Members
    Members
    • Achievement Levels
    • Benefits of Membership
    • Feedback and Support
    • Members Area
    • Personal Blogs
    • What's New on element14
  • Learn
    Learn
    • eBooks
    • Learning Center
    • Learning Groups
    • STEM Academy
    • Webinars, Training and Events
  • Technologies
    Technologies
    • 3D Printing
    • Experts & Guidance
    • FPGA
    • Industrial Automation
    • Internet of Things
    • Power & Energy
    • Sensors
    • Technology Groups
  • Challenges & Projects
    Challenges & Projects
    • Arduino Projects
    • Design Challenges
    • element14 presents
    • Project14
    • Project Groups
    • Raspberry Pi Projects
  • Products
    Products
    • Arduino
    • Avnet Boards Community
    • Dev Tools
    • Manufacturers
    • Product Groups
    • Raspberry Pi
    • RoadTests & Reviews
  • Store
    Store
    • Visit Your Store
    • Or choose another store...
      • Europe
      •  Austria (German)
      •  Belgium (Dutch, French)
      •  Bulgaria (Bulgarian)
      •  Czech Republic (Czech)
      •  Denmark (Danish)
      •  Estonia (Estonian)
      •  Finland (Finnish)
      •  France (French)
      •  Germany (German)
      •  Hungary (Hungarian)
      •  Ireland
      •  Israel
      •  Italy (Italian)
      •  Latvia (Latvian)
      •  
      •  Lithuania (Lithuanian)
      •  Netherlands (Dutch)
      •  Norway (Norwegian)
      •  Poland (Polish)
      •  Portugal (Portuguese)
      •  Romania (Romanian)
      •  Russia (Russian)
      •  Slovakia (Slovak)
      •  Slovenia (Slovenian)
      •  Spain (Spanish)
      •  Sweden (Swedish)
      •  Switzerland(German, French)
      •  Turkey (Turkish)
      •  United Kingdom
      • Asia Pacific
      •  Australia
      •  China
      •  Hong Kong
      •  India
      •  Korea (Korean)
      •  Malaysia
      •  New Zealand
      •  Philippines
      •  Singapore
      •  Taiwan
      •  Thailand (Thai)
      • Americas
      •  Brazil (Portuguese)
      •  Canada
      •  Mexico (Spanish)
      •  United States
      Can't find the country/region you're looking for? Visit our export site or find a local distributor.
  • Translate
  • Profile
Passive Components
  • Technologies
  • More
Passive Components
Forum Hey, Guys, I'm stumped It
  • Blog
  • Forum
  • Documents
  • Events
  • Polls
  • Members
  • Mentions
  • Sub-Groups
  • Tags
  • More
  • Cancel
  • New
Passive Components requires membership for participation - click to join
Actions
  • Share
  • More
  • Cancel
Forum Thread Details
  • Replies 26 replies
  • Subscribers 83 subscribers
  • Views 2067 views
  • Users 0 members are here
  • logo
  • resistor
  • manufacture
Related

Hey, Guys, I'm stumped It

phoenixcomm
phoenixcomm 7 months ago

imageOk, it claims to be a 0.22Ω 3watt power sand resistor, with 3 legs. (so starting at the top and going clockwise, 1 at the top, 2 on the right, and 3 on the left)

My fluke 113 says no it's 0.38Ω between 1 and 2, as well as between 1 and 3, and 0.59/0.60Ω between 2 and 3. 

My HP3435A  set on the 20Ω scale says it's 0.37Ω between 1 and 2, and 0.38Ω between 1 and 3, and 0.59Ω/0.60Ω between 2 and 3.

Something is not right. 

and Please look at the logo, so I can figure out who made the stupid thing..

oh btw the wires go all the way through the body and are about 1" long on the reverse side. 

Thanks again. Cris

  • Sign in to reply
  • Cancel

Top Replies

  • jc2048
    jc2048 7 months ago +5
    As you've got two meters, perhaps just do your own four-wire measurement. Set a PSU to constant-current, use one of your meters to measure the current through the resistor, the other to measure the voltage…
  • beacon_dave
    beacon_dave 7 months ago in reply to jc2048 +5
    Push pull amplifier designs appear to use them. Here is a Sony receiver design using a similar device. https://www.petervis.com/Amplifiers/sony-str-k740p/how-to-fix-sony-amplifier-protect-mode-error…
  • michaelkellett
    michaelkellett 7 months ago +4
    Just guessing but: lets assume your leads have about .15 ohm resistance. then its a 0.22 R from 1 to 2, a second 0.22R from 1 to 3 (they both read about 0.37) so from 2 to 3 its 0.44R + the lead reistance…
  • michaelkellett
    michaelkellett 7 months ago

    Just guessing but:

    lets assume your leads have about .15 ohm resistance.

    then its a 0.22 R from 1 to 2, a second 0.22R from 1 to 3 (they both read about 0.37) so from 2 to 3 its 0.44R + the lead reistance of 0.15 giving a readfing of 0.59.

    MK

    • Cancel
    • Vote Up +4 Vote Down
    • Sign in to reply
    • Cancel
  • dougw
    dougw 7 months ago

    If you short 2 and 3 do you get 0.22 ohms between 1 and the short?

    • Cancel
    • Vote Up +1 Vote Down
    • Sign in to reply
    • Cancel
  • Jan Cumps
    Jan Cumps 7 months ago in reply to michaelkellett

    Yes, 0.22 is tricky to measure.
    it isn't easy to measure these very low resistor values anywhere close to their real value with 2-wire meters. Even if you push hard on the contacts.

    "The measurement of very large or very small quantities is always difficult, and resistance measurement is no exception. Values above 1GΩ and values below 1Ω both present measurement problems."

    "When measuring larger resistance values this additional lead resistance error can be ignored, but as you can see from the chart below, the error becomes significantly higher as the measured value decreases, and totally inappropriate below 10Ω."

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Cancel
  • Jan Cumps
    Jan Cumps 7 months ago

     phoenixcomm , does it have pins at the other side too?

    (ah, saw in your post that you mentioned them)

    https://www.shutterstock.com/image-photo/cement-power-resistor-three-pins-on-1570576969

    image

    • Cancel
    • Vote Up +3 Vote Down
    • Sign in to reply
    • Cancel
  • beacon_dave
    beacon_dave 7 months ago
    phoenixcomm said:
    and Please look at the logo, so I can figure out who made the stupid thing..

    Looks similar to the old Pana Sonic 
    image

    • Cancel
    • Vote Up +2 Vote Down
    • Sign in to reply
    • Cancel
  • Jan Cumps
    Jan Cumps 7 months ago in reply to beacon_dave

    You seem to be spot on with the logo (source):

    image

    • Cancel
    • Vote Up +1 Vote Down
    • Sign in to reply
    • Cancel
  • phoenixcomm
    phoenixcomm 7 months ago in reply to beacon_dave

    Thank you dave

    • Cancel
    • Vote Up +1 Vote Down
    • Sign in to reply
    • Cancel
  • dang74
    dang74 7 months ago in reply to dougw

    I was thinking the same except I would suggest shorting pin 1 to pin 2.  This would put the 0.38 OHM resistance in parallel with the 0.6 OHM resistance which of course is very close to the 0.22 OHM.

    • Cancel
    • Vote Up +2 Vote Down
    • Sign in to reply
    • Cancel
  • rsjawale24
    rsjawale24 7 months ago

    Apologies for the bad drawing, I had to do it in MS paint without a stylus/pen.
    Assuming the connections are as shown below
    image

    R12 = R13 = 0.38 ohms
    And R23 = 0.6 ohms.
    However as per the specs, the entire resistor should be 0.22 ohms.
    As mentioned by dowg, if you short 2 and 3, the resistors will be in parallel and value would be 0.38/2 = 0.19 ohms. 

    R23 = 0.6 ohms also makes sense, as both resistors will be in series and so 0.38*2 = 0.76 which is close to 0.6 with not so precision DMM.
    Also, to measure such small resistance values, you would need precision ohmeter/DMM otherwise the lead resistances from the probes will not give you a correct reading.

    • Cancel
    • Vote Up +1 Vote Down
    • Sign in to reply
    • Cancel
  • jc2048
    jc2048 7 months ago

    As you've got two meters, perhaps just do your own four-wire measurement.

    Set a PSU to constant-current, use one of your meters to measure the current through the resistor, the other to measure the voltage across the resistor, and work out the resistance from Ohm's law.

    • Cancel
    • Vote Up +5 Vote Down
    • Sign in to reply
    • Cancel
>
element14 Community

element14 is the first online community specifically for engineers. Connect with your peers and get expert answers to your questions.

  • Members
  • Learn
  • Technologies
  • Challenges & Projects
  • Products
  • Store
  • About Us
  • Feedback & Support
  • FAQs
  • Terms of Use
  • Privacy Policy
  • Legal and Copyright Notices
  • Sitemap
  • Cookies

An Avnet Company © 2023 Premier Farnell Limited. All Rights Reserved.

Premier Farnell Ltd, registered in England and Wales (no 00876412), registered office: Farnell House, Forge Lane, Leeds LS12 2NE.

ICP 备案号 10220084.

Follow element14

  • X
  • Facebook
  • linkedin
  • YouTube