Calibration of a scale is a procedure in which a licensed scale technician uses a known cal test weight certified by the State of North Carolina Bureau of Weights and Measures, to test and adjust the response of a mechanical or electronic weighing system to the following tests; The display indicator must show zero when there is no weight on scale. When a known weight is applied the indicator must display the exact amount of applied weight within a specific tolerance. When weight is applied or removed incrementally the scale must display the weight equal to that on the scale within the specified tolerance mentioned above.
Not all companies are created equal. We have been selling, repairing, and renting scales since 1980. Calibration is actually an important component of your scales accuracy and dependability. That's why we train our technicians on the proper way to calibrate scales and we use certified test weights for maximum accuracy. Every so often someone will ask do you need real professional weight to put on a scale and sometimes in a pinch you might be able to get away without a weight but generally it is highly recommended that you use weights for scale calibration. Not just any weights, they ideally need to be certified weights or weight kits. The procedure is roughly the same for most average size scales. First, make sure the scale is empty and the display shows zero. Then add a known weight and notice what the display shows. If it is within tolerance, no adjustment should be necessary. If it is out of tolerance, adjustments will need to be made to bring it within tolerance. Our factory trained tech's also pay attention to the weight as it is placed on the scale to see if it is consistent as each one is added and we also like to place the weight on different corners of the weighing platform. This is generally true no matter what brand you're talking about from Avery Weigh Tronix scale calibration to Rice Lake Weighing Systems. Sometimes when you are dealing with truck scale calibration it can involve a few more steps such as adjusting sections but the basic principle is the same.
For the most part you should call in the professionals when it comes time to cal a scale. The pro's have the experience and the right equipment. From time to time we get asked for operator manuals or user guides for scales. Most of the time the cal instructions are listed in those manuals, however sometimes they are not. Many times if we get a request from someone looking for Salter scale calibration instructions we will refer them to the manufacturer website since a number of the manufacturers have started placing the manuals online. It really depends on the type of scale and the location the customer is calling from.
It is really
rewarding every time a new customer calls or emails us looking for
scale calibration services. We're located in Sanford but we have customers all around the triangle area such as Raleigh, Durham, Burlington, Smithfield, Fayetteville, and more. We obviously provide industrial scale calibration and scale repairs but one example you might not
think about is medical scales. We do have quite a few local customers
in the healthcare industry who call us looking for physician scale
calibration services. This is something that we can certainly do
since we have factory trained technicians and certified test weights.
We are sometimes asked how to check scale calibration or how often to do scale calibration and the answers can vary depending on your situation. For most scales it is a good idea to have them checked at least a couple times a year. Depending on how important scales are in your business, you might want to have our factory trained technicians check them every month or every quarter. To check the scale you simply put an item on the scale and see what it weighs. Ideally this would be a certified test weight or it can be some other "known" weight. Then check to see if the scale is displaying the right weight. Another example might be if you own a portable truck scale, you should probably calibrate that scale every time you move it from one location to another location. Or at least check it with a known weight to make sure the accuracy is still acceptable.
SCALE CALIBRATION PROCEDURE
One of the tremendous advantages that our scale repair and service provides you is factory training and certified scale calibration weights and weight kits. When we check your equipment it is checked with accurate weights and the accuracy is written down on our scale calibration report and we place labels on your devices which shows the date they were checked and the due date for the next service.
One question we are asked sometimes is how do I calibrate my scale without weights? There are two examples we can look at. First, if you are lucky enough to have a laboratory balance that includes internal calibration, technically you don't have to posess any weights because the weights are already in the balance. Another example would be using a known weight. Say you are out in a warehouse that has two or three floor scales. If one of the scales needs to be checked, just place an item on one of the other floor scales and get a weight. Place that item on the scale you need to calibrate. This is not a perfect solution but it should work until you can get a scale calibration company in with real test weights.
Hopefully some of the highlights above have assisted you with calibrating digital scales. We have been servicing and repairing scales throughout much of North Carolina for over thirty five years. We encourage you to browse our website and contact us for your weighing needs.
is scale calibration?
Calibration of a scale is a procedure in which a certified scale technician uses known weight certified by the State of North Carolina Bureau of Weights and Measures, to adjust the response of a mechanical or electronic weighing system to the following tests; The indicator must show zero when there is no weight on scale. When a known weight is applied the indicator must display the exact amount of applied weight. When weight is applied or removed incrementally the scale must display weight equal to that on the scale display.
is calibration needed?
All scales ideally need to be calibrated when first placed into service to insure accurate operation. Any scale will drift away from its original calibration in time. Wear of mechanical components, age and degree of use, all contribute to calibration drift. Many states require that any scale used to buy/sell based on weight must be NTEP approved and inspected and certified as to itís accuracy. Normally, we recommend calibration every quarter by a trained scale technician with certified test weights.
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How often must I calibrate?
There are several factors to consider when deciding on frequency of scale calibration testing. Is the scale operating in a hostile environment? How much is this equipment being used, one two, three shifts, or only several times a week? Are there Quality Control parameters which must be maintained such as ISO 9000? How long can your company afford to allow your scale equipment to operate with a possible error in the weight reading(s)? After factoring all the information above, many customer's feel calibration service once a quarter is ideal.
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How can I set up my weighing equipment for regular calibration?
Central Carolina Scale, Inc. will assist in setting up your custom scale service agreement program by taking into consideration all of the above questions. It is recommended that scales be calibrated quarterly. Central Carolina Scale, Inc. will perform the tests as prescribed in the service agreement statement.
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Calibration & Test Procedures
Platform: The scale deck should be wiped free of foreign materials and checked for obstructions. Check under and around the platform for foreign materials. Remove any items that will adversely effect weighing accuracy. Pit type scales should be checked for clearance around the pit walls and foreign materials removed if necessary. Mechanical scales should be checked for freedom of movement in all directions.
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Marking: All scales should be properly marked with the capacity and count by on the display panel or the serial tag. "NTEP Legal for trade" scales must be properly marked in accordance with Handbook 44 requirements with a CoC number.
Load Stops: Visually inspect the over load stops for proper
clearance. Small bench scales should be loaded to capacity to determine
if the stops have sufficient clearance and with capacity weights
on the scale, gently push the platform to insure that the stops
are engaged with very little movement required.
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Overview: Test procedures according to CCS, Inc. will be adhered to, unless other test procedures are requested by the customer. All tests should be completed and the initial error properly marked before corrections are started.
calibration information or to schedule a service calibration routine
for your scales or lab balances, please give the service team at
Central Carolina Scale a call today at (919) 776-7737