What is better External Calibration verses Internal Calibration

www.scaleman.com is your source for precision lab balances and calibrations weights.
We'll show you how to calibrate the GP-20K precision industrial balances and just how accurate the balance is when you do an external calibration verses an internal calibration. Internal calibration works much better for analytical balances with weighing capacities up to 300 grams but once you start using high capacity precision balances of 12,000g or greater you really need to calibrate with external calibration weights. If you calibrate external we high recommend that you disable the internal calibration so you don't ever write over the external calibration data parameters. Precision Weighing Balances is an authorized A&D Weighing Dealer and we offer a full line of calibration weights at www.calibrationweight.com
The GP20K used in this video can be purchased at balance.balance...

[@ronniesciortino7587]

Excellent demonstration. Very educational and informative.

[@somaday2595]

Regarding the accuracy of internal cal weights, I have scrapped weights used in the older analytical non-strain gauge (actual & electro) balances used for setting the various weight ranges and found them to all agree with one another whether they be Denver, Mettler, Ohaus or Sartorius, (I never had an older A&D balance to scrap). I had asked Mettler and Sartorius tech about the cal class the internal non cal wts used and they would not give an answer but said they far exceeded standards. Nebulous answers from metrology firms.
Scrapping a Mettler AT400, I thought the internal cal wts in this would be super, but when checking, they seemed off their mark. Inquiring, Mettler told me the internal cal wt was quite accurate, (as in better than Class E1), but not necessarily an expected wt such as 200 or 400g; rather, the actual wt used for calibration was stored in the internal cal software and displayed a massaged expected wt like the 200 or 400g. So, it would seem using the internal cal wts from a newer, strain gauge based balance, at least from a Mettler, probably would not work unless that internal number assigned and locked away in the software could be accessed. Oh well.

[@balancesDOTcom]

I agree "Nebulous answers from metrology firms". External calibration is the preferred method of calibration since an external weight can be verified of the True Mass and the NVLAP calibration certificate documents "True Mass As Left". Review this NVLAP Cert example at scaleman.com/index.php/aitdownloadablefiles/download/aitfile/aitfile_id/857/
The internal weight can be scratched over a period of time and the weight can also get magnetized since most of the internal weights are on a metal hanger. When metal rubs against metal the weight can be magnetized.
ISO/IEC 17025 testing and calibration procedures only allow external calibration for laboratory balances.
Although the EURAMET Calibration Guide No.18 Version 4.0 is for Europe I believe the "Guidelines on the Calibration of Non-Automatic Weighing Instruments" is a good read and you can download it at www.euramet.org/Media/docs/Publications/calguides/I-CAL-GUI-018_Calibration_Guide_No._18_web.pdf
Please visit calibrationweight.com/ or scaleman.com/balances/calibration-weights.html if you need to purchase calibration weights. We are an Authorized Troemner Dealer.

[@kennedymutua3763]

Thank you for this vital information

[@balancesDOTcom]

+Kennedy Mutua Kennedy thank you for your kind comments about our video. This youtube videos was created by us. We are Precision Weighing Balances and you can see the full line of AND GP Scales by visiting balance.balances.com/scales/646 and scroll to the bottom of the web page and we will see you can select from 14 different GP Industrial Balances to meet your specific weighing needs. Precision Weighing Balances is a Authorized A&D Weighing Dealer and you can see all the AND Weighing products we offer at and.balances.com/

[@sylviojr]

Thank you. Very useful information.

[@balancesDOTcom]

+Sylvio Jr Thanks for your comments. If you need calibration weights they can be ordered at calibrationweight.com or scaleman.com/balances/calibration-weights.html

[@ezzatollahshahsavari1368]

how we can download this use full video file ?

[@balancesDOTcom]

Thank you for liking our video. Precision Weighing Balances created this video and we ask that you view it from our youtube channel. You can also use this link ruclips.net/video/QPOYhuf1AuQ/видео.html I am sorry but we only want the video shown on our youtube channel and it should not be downloaded violating copyright protection.