AND FX-120iN is one of the lowest cost Legal for Trade digital scale with 122 grams weighing capacity displaying to 0.001 grams division and the verification scale division of 0.01 grams. This digital balance is popular for weighing precious metals (gold, platinum, palladium, rhodium) in the jewelry and pawnshop industry when the metal is bought or sold by weight. Additional uses would be for pharmacies requiring a Class "A" prescription scale to maintain their pharmacy license when the requirements are a weighing device with a minimum tolerance of 0.1 grains or 6 milligrams.
The FX120iN legal for trade digital scale is NTEP approved (National Type Evaluation Program) complying with the applicable technical requirements of "NIST Handbook 44: Specifications, Tolerances and Other Technical Requirements for Weighing and Measuring Devices".
The "d" (value of scale division) is 0.001 grams and the "e" (value of verification scale division) is 0.01 grams. When "d" and "e" are not the same value the last division on the scale's display is "boxed". If you placed a gold ring on the FX120iN the display might read 7.03 grams. So the item weighs 7.031 grams and since "d" and "e" are not equal the last decimal is uncertain. A pawnbroker could tell the customer - you have 7.03 grams.
The FX-120iN is a Class II weighing devices. Handbook 44 defines a Class II balance as any weighing device with 10,000 - 100,000 verified divisions. Since the FX-120iN weighs up to 122 grams and "e" is equal to 0.01 grams it is therefore 12,200 verified divisions. All this information can be verified by downloading the CofC # 08-045A2
&Measures Inspectors uses the guidelines in Table 8 of section 2.20 Scales in NIST Handbook 44, 2.2 Theory of Tolerances in Appendix A for determine to applicable scale for the weighing application such as weighing gold. You can download sections of NIST Handbook 44 - 2012 Edition here.
Table 8 says that the smallest item weighed on a class II scale with a verification scale division size of 0.1 g should weigh at least 5 grams (50 divisions) - the FX1200iN meets this description. The smallest item weighed on a class II scale with a verification scale division size of 0.01 g should weigh at least 0.2 grams (20 divisions) - the FX120iN meets this description.
The Theory of Tolerances states that the tolerance allowed on a commercial weighing device should not cause economic injury to either the buyer or the seller. A class II scale with a verification scale division size 0.1 gram is allowed 1 division (0.1 g) maintenance tolerance for weights between 0 and 500 grams. So if you had a known weight and we'll say a 100g calibration weight weighed on a LFT scale with a verification scale division of 0.1 gram the scale could read 99.9g, 100.0g or 100.1g and be within tolerance. At the current market prices for gold ($1228.70 per troy ounce on 3/1/2016), that tolerance would allow a monetary error in excess of $3.95 on every transaction. Since one  troy ounce = 31.1034768 grams therefore $1228.70 / 31.1034768 = $39.503 per gram and if one used a scale verified division of 0.1 gram you need to divide $39.503 by 10 to equal $3.9503 for each tenth of a gram division. Since the FX-120iN is verified to 0.01g the monetary error now drops to 39 cents.
For this reason, the Minnesota Weights & Measures Division requires that scales used for precious metal transactions have an "e" less than or equal to 0.01 g and the A&D Weighing FX-120iN meets the requirements.
You should always check with your local state or county Weights & Measures office to determine their exact requirements for a scale. Many states like Minnesota have very strict penalties for any person buying or selling precious metals by weight and using the wrong scale could result in a criminal penalty if found guilty of imprisonment for not more than three years or to payment of a fine of not more than $40,000, or both.
One of the reason there are not a lot of digital scales that are legal for trade is because the scale has to really measure correctly. The scale needs to incorporate a high quality precision weigh sensor and electronics. During evaluation process a load of one-half capacity is placed on the digital scale more than 100,000 times testing for accuracy and
functionality. There are also device markings and design requirements to prevent the scale from being calibrated once placed in service. This is achieved by sealing the FX-120iN by threading a wire security seal through two screws on the RS-232 serial interface plate and scale
housing. This prevents access to the calibration switch inside the device.
When the FX-120iN digital balance is first installed it should be calibrated to ensure accurate weighing results. We offer a full line of calibration weights including the recommended OPTIONAL 100 gram calibration weight for the FX-120iN. Every location in the world is positioned differently to "magnetic north" and therefore the acceleration of gravity is slightly different. Some Weights & Measures Inspectors will calibrate your FX-120iN when they come and inspect the balance and put it into service. Other states required only a licensed certified scale technician to perform calibration and they charge up to $225 just to place the calibration weight on the weighing platform. Other states will allow you to calibrate your own balance. If you are allowed to calibrate your own balance make sure you watch our youtube video how we walk you through the calibration process. Instead of buying the 100g ASTM Class 1 with NVLAP Certificate you can probably save money buy purchasing the 100g ASTM Class 2 (± 0.50 mg) with NO Certificate for $68 in the option section below. Again you should check with your Weights & Measures Division about calibration especially since calibration weights are not returnable.
We understand purchasing a legal for trade balance is a major capital expense and if you have any questions give us a call and one of our weighing experts can discuss your weighing application and get you the most affordable balance for your weighing needs.
There is a lot of confusion when it comes to buying the FX-i NTEP digital balances and hopefully this youtube video above will clear those issues up do you don't purchase the wrong balance.
In the youtube video above we take you step by step how to calibrate the AND Weighing FX-300iN Legal for Trade digital scale. You'll see how to open the RS-232 serial interface plate and press the calibration buttion to initialize calibration. The calibration procedure is similar for all the FX-iN Series except the only difference would be the exact calibration weight required for the particular model. The steps to perform calibration are entirely different compared to the Non-NTEP models for the FX-i Series.
Top View of FX-i series A&D Precision Balance
The A&D FX/iN Legal For Trade NTEP approved Class 2 series precision balances come in several weighing capacities to accommodate your specific weighing needs. Choose between 0.01 gram or 0.001 gram increments. New FXi Precision scales with milligram resolutions include a small breeze break for precise weighing. Get accurate weighing results with the latest precision scale from A&D!
In the youtube video above we offer an overview of the AND Weighing FX-300iN discussing the sprint bubble and how important it is to level the balance, the 6 tactile keypads and the functions of these keys. Watch how to change the weigh modes and how simple it is to go from grams to ounce to grains. See the spill guard / plastic cover, the two(2) adjustable feet, RS232 serial interface, weigh below port and many other features that are available with most of the FXi/FZi Series.
The FXi-10 small breeze break comes standard with the FX/FZi milligram balances(0.001 gram) and can be upgraded by purchasing the optional FXi-11 large breeze break. The FX/FZi precision balances (those that increment in 0.01 gram divisions) do not come with any windshield, but can be purchased with either optional accessory FXi-10 small breeze break or FXi-11 large breeze break.