Scientech Labs - Mistakes Made in Testing Balances by Doug Morse
NTEP CERTIFIED SCALES
View the Zeta NTEP Jewelry Scale brochure
View the Zeta NTEP Pharmaceutical Scale brochure
Scientech has now coupled NTEP (legal-for-trade) certification with our new revolutionary Zeta Series design for precision jewelry balances and for pharmacy compounding and pill counting. This unique marriage gives you the advantage of a very accurate scale, which complies with all the applicable technical requirements of Handbook 44 while possessing the ability to last decades under extreme abuse. This exclusive design is so impressive that these hardy models have been issued a patent and carry a 5-year North American warranty or a 2-year international warranty.
Under NTEP Certificate Number 07-017, two of our 1mg Zeta models now carry the NTEP non-computing jewelry scale, and one of our 1mg Zeta models has the non-computing scale for prescription compounding and pill counting. All models possess the Accuracy Class II designation. Each unit can be sealed off with a metrological seal by a State Weights and Measure inspector to prevent undetected access to the calibration function of the scale as well as possessing a tamper proof badge for all required information.
Please note that each Zeta scale has a weighing sensor with a suspension system which cannot be broken by customer abuse or by dropping a weight onto the weighing pan. As you might know, the highest failure mode for any analytical (0.1mg) or semi analytical (1mg) balance is a broken suspension system due to them having fragile pivots, pullers, flexures, or bearings. Then when any weight is dropped on the weighing pan (this is called shock loading) or by user misuse, these fragile pivots, pullers, flexures, bearing will break. The way our competitors try to handle this concern is to state that they have "overload" protections. However, overload protection does not protect against shock loading or customer abuse. Therefore, the damaged scale is not covered under warranty.
In contrast, the new technology used in the Zeta NTEP scales eliminates any pivots, pullers, flexures, or bearings. Therefore, it is not possible to break the suspension system of these rugged models. Please see the streaming video on the homepage of this web site to see what these scales can do. All observers who have seen this video have been stunned that the demonstrated abuse does not harm these scales.
In addition, each unrivaled Zeta NTEP model is handcrafted in the USA and retains all the accuracy, durability, and user-friendly standard features you have come to expect from Scientech. Also you will be assured by knowing that you are backed by an ISO9001 manufacturer.
OEM Gravimetric Sensors
Scientech is a world leader in providing OEM weighing sensors for a multitude of intregrated weighing applications. Whether you want high accuracy, high speed, small foot prints, or extreme ruggedness, we can meet your need. Custom designs with varying capacities, readabilities, footprints, and outputs are available to satisfy your specific requirement.
Our newest OEM offering is our brand new Zeta sensor which provides a major breakthrough in the design of analytical (0.1mg) and precision (1mg and 10mg) sensors. This breakthrough is that we have developed a weighing sensor with a suspension system which cannot be broken by dropping a weight onto the weighing pan.
As you might know, the highest failure mode for any analytical (0.1mg) or semi analytical (1mg) balance is a broken suspension system due to them having fragile pivots, pullers, flexures, or bearings. Then when any weight is dropped on the weighing pan (this is called shock loading) these fragile pivots, pullers, flexures, bearing will break. The way our competitors try to handle this concern is to state that they have "overload" protection. However, overload protection does not protect against shock loading. Therefore, shock loading is considered customer abuse and is not covered under warranty.
In contrast, the new technology used in the new Zeta OEM sensors eliminates any pivots, pullers, flexures, or bearings. Therefore, it is not possible to break the suspension system of these rugged models with shock loading. This has been clearly proven by demonstrations of extreme abuse by repetitively dropping a 2kg weight on the weighing pan of a 210g x 0.1mg sensor from a height of 25-37mm. All observers have been stunned that this severe abuse did not harm the sensor, and everyone agrees that our competitors' models would certainly break under these conditions. Scientech now has a streaming video of this demonstration which you can see on the homepage.
The foundation for this new technology is based on a direct-loading weighing cell concept, which differs dramatically from a normal lever sensor design. The result is a high quality, OEM weighing sensor.
Zeta Series Electronic Balances
View the Zeta Series brochure PDF
Scientech is announcing a new Series of electronic balances based on a new, revolutionary weighing technology developed by Scientech. A patent for this new technology has been issued.
The foundation for this new technology is based on a direct-loading weighing cell concept, which differs dramatically from a normal lever sensor design. When used in combination with Scientech's unique and unequalled displacement detection system and our digital servo, the result is a high quality, weighing sensor that can easily handle readabilities even down to 0.1mg for less cost. The attractive quality of this new technology is demonstrated by the CE mark of conformity, Scientech's ISO 9001 registration, and a new 5-year North American warranty.
Branded the "Zeta Series", this new line comprises an impressive list of both single and dual range models. With capacities ranging from 80g to 600g and readabilities from 0.1mg to 0.01g, these 14 new models sport an impressive array of standard features. These features include an analytical windscreen with three glass sliding doors for analytical models, RS232 data interface, multiple units of measure, GLP/GMO/ISO compatibility, selectable filter settings, exclusive real-time temperature compensation, automatic calibration software, percent weighing, capacity tracker, and many more.
SM (Semi-Micro) Models
View the 12000 Series brochure PDF
Scientech is announcing eight semi-micro balance models. Semi-micro balances are analytical balances with a readability of 0.01mg (10µg).
The foundation for this high performance SM Series is Scientech's unique and unequalled displacement detector, which is the heart of our state-of-the-art, self-adjusting, digital servo. The result is a ten-fold increase in weighing performance while maintaining our proven, simple, easy to use, operator interface. The attractive quality of this new design is demonstrated by the CE mark of conformity along with Scientech’s ISO 9001 registration.
The SM Series comprises an impressive list of both single and dual range units. What is even more remarkable is every dual range model possesses Scientech’s exclusive Floating Tare™ feature. This powerful option gives you two balances in one unit. Used hand-in-hand with autoranging, Floating Tare™ provides low range readability (0.01mg) throughout the entire high range capacity of the balance. Access Floating Tare™ with the press of a button and you have ten times more resolution anywhere within the high range domain.
Scientech's new SM Series embraces these four exceptional models:
- SM50 – Single range 50g x 0.01mg
- SM99 – Single range 99g x 0.01mg
- SM50IW – Single range 50g x 0.01mg with internal calibration
- SM90IW – Single range 99g x 0.01mg with internal calibration
- SM124D – Dual range 40g x 0.01mg & 120g x 0.1mg with Floating Tare™
- SM128D – Dual range 80g x 0.01mg & 120g x 0.1mg with Floating Tare™
- SM 124DIW – Dual range 40g x 0.1mg with internal calibration and Floating Tare™
- SM 128 DIW – Dual range 80g x 0.1mg with internal calibration and Floating Tare™
Each model includes an impressive array of standard features including an analytical windscreen with three glass sliding doors, RS232 data interface, GLP/GMO/ISO compatibility, selectable filter settings, exclusive real-time temperature compensation, automatic calibration software, percent weighing, capacity tracker, and many more.
Series 12000 Electronic Balances
View the Series 12000 brochure PDF
Scientech is announcing a new Series of electronic balances called our Series 12000.
The foundation for this new line is Scientech’s unique and unequalled displacement detection system and our digital servo. The result is a high quality balance that can go as low as 0.01mg for less cost. The attractive quality of this new technology is demonstrated by the CE mark of conformity along with Scientech’s ISO 9001 registration.
This impressive new Series includes:
With the emphasis in the market for high quality, low cost products, you cannot go wrong with Scientech’s new Series 12000 line of electronic balances.
- 46 models in both single and dual range configurations
- Four semi-micro (0.01mg) models
- Capacities range from 50g to 12,000g
- Readabilities from 0.01mg to 0.1g
- All dual range units feature our exclusive Floating Tare™ feature
- The latest technology
- Twelve 0.1mg and 0.01mg models which have internal calibration weights as a standard feature
- A new look with an attractive color scheme
- A much larger LCD display with the numerals having a height of 23mm (about 1 inch)
- Two tare buttons
- RS232 data interface
- GLP/GMP/ISO compatibility
- User selectable filter settings
- Capacity tracker
- Percent weighing
- Parts counting
- Eight units of measure (g, kg, mg, lb, oz, troy oz, carats, and pennyweight)
HC Series Electronic Scales
View the HC Series brochure PDF
Scientech is announcing a new line of electronic scales branded the HC Series.
The new HC Series is a high-capacity, high-precision, robust line of scales which consists of four, valued priced models. Capacities span an extensive range of 12kg to 30kg with a precision of 0.1g while sporting a large stainless steel weighing platform. Usually a readability this fine is only found in fragile laboratory instruments possessing smaller capacities and smaller weighing pans.
The four new models, the SHC12 (12kg), SHC16 (16kg), SHC20 (20kg), and SHC30 (30kg), all have steel construction for durability and a large, bright, vacuum fluorescent display, which is easy to read in all lighting conditions including bright sunlight. The 9” x 13” (216mm x 318mm) rectangular, stainless steel, weighing platform accommodates large loads and includes anti-shock protection. In addition, these sleek looking scales have a simple to use, water resistant keyboard for ease of operation along with a full alpha-numeric menu display. For those customers wanting to do a specific gravity or density determination measurement with manual calculations, these sturdy models can be a handy tool. An optional specific gravity software program can be purchased which will do the specify gravity calculations automatically.
All models sport an impressive array of standard features such as parts counting, RS232 bi-directional serial interface, multiple units of measure, adjustable filter settings, one key calibration, auto zero function, 100% subtractive tare, adjustable feet, and level bubble. The attractive quality of this new Series is also demonstrated by the CE mark of conformity along with Scientech’s ISO9001 registration.
Tip Sheet on Good Measurement Practices When Using Electronic Balances
(As quoted from the Mass Standards Handbook by Troemner, 3-015BKT rev 1/03)
There are numerous steps that one can take in order to improve the quality of a mass measurement system. However, they usually fall within three main categories: the equipment, the environment, and the operator. If even one of these areas in neglected, it can have a dramatic negative impact on your results. Although these suggestions are not meant to be all encompassing or all-inclusive, the improvements that can be made following these simple guidelines are extraordinary.
- Select weights that have a tolerance that is one third or better than the accuracy you require for your application. This way the error of the weight will not dramatically impact the quality of your measurements.
- The equipment must be of sufficient readability to calibrate or measure the weight or sample under test.
- The balance should be placed on a stable platform free from the effects of vibration. The most common type of setup involves placing the instrument onto a balance table that is constructed of marble or granite.
- Never use a balance or scale as soon as it is turned on (plugged in). The internal electronic components need to stabilize and “warm up” for at least 24 hours once the equipment has been energized. Troemner recommends that you leave this instrument plugged in twenty four hours a day, seven days a week.
- Never use a balance that has been idle for several hours without first "exercising it" and calibrating it. A balance is exercised by repeatedly placing and removing weights from the balance pan. We recommend that this be done at least ten times each with a weight that is 100% of the max capacity of the balance. After exercising, the balance should be calibrated. If these two techniques are consistently employed, a noticeable improvement will result in both linearity and stability of the measurement.
- When weights are not in use, store them in the case in which they were supplied. If the weights were not supplied with a case, either purchase a case or use a clean container to protect the surfaces. This will keep airborne particles from getting on your weights between uses. Weights should be in thermal equilibrium with the balance so store weights near your balance. Another option is to leave calibration masses commonly used inside the weighing chamber when not in use. This assures your weights are in thermal equilibrium with the balance producing a better measurement.
- The more stable your environment, the better your measurement results. Changes in temperature, pressure, and humidity affect balance performance and weight stability. Ideal room conditions are 20º C with a relative humidity between 45% and 60%. Fluctuations in temperature should not exceed 1º C per hour. Humidity fluctuations should not exceed 10% per hour.
- Balances should not be placed in close proximity to anything that shakes, vibrates, or stirs violently. Avoid placing your equipment near centrifuges, vortexers, or shakers.
- Do not place your balance and/or scale near anything that generates heat. Heat will cause the balance chamber to warm and due to the effects of the thermal expansion introduce large errors into your measurement. Do not place the balance near a window. Sunlight can penetrate the window, warm the balance chamber at different rates during the day, and affect the quality of your work.
- Avoid placing the balance near sources of drafts, extreme air currents, or near air-conditioning vents. These positions can cause your readings to be unstable and can dramatically cool the balance chamber when the air-conditioning system begins to run.
- The measurement environment should be clean and free of excessive contaminants. Contaminants such as dirt and grease can adversely affect the weight of an object.
- Never touch a weight with your bare hands. Oils and contaminants from your hand will be transferred to the weight and introduce a significant error. It is recommended that all weights be manipulated with gloved hands or forceps. The two types of gloves that are commonly used and accepted are either latex (powderless) or cotton. Avoid any metal to metal contact when handling or storing weights. This will cause scratches that may introduce error. All weight forceps and weight lifters should be either nonmetallic (plastic or wood) or if metal, covered with a soft protective coating or material to avoid scratches.
- Place the weight or sample near the center of the balance pan. A small offset from center can have a pronounced effect and introduce undue variation.
- Take special care not to breathe onto the weight or into the balance chamber. Back away from the instrument. This will prevent any thermal transfer of heat from your breath or body to the balance, the weight, or the sample.
- Time your measurements. Consistent sample times will provide more consistent measurement.