13 piece Class 1 calibration weight set (PWB7216-1W), includes NVLAP Certificate. Typical lead time is 7 to 10 business days from the date order is placed to shipping from Troemner's accredited NVLAP metrology lab.
This weight set consists of the following weights - 1 kg, 500 g, 2-200 g, 100 g, 50 g, 2-20 g, 10 g, 5 g, 2-2 g, 1 g. The total capacity of the weight set is 2110 grams. Supplied in handcrafted wood case. Includes a compartment for a polycarbonate case which holds weights 500 g and below. 1 kg weight is held in an individual polycarbonate case inside a felt-lined cutout.
Balances should always be checked with reference weights so you know your laboratory balance is weighing accurately. Checking the accuracy of your laboratory balance can accomplished by carefully placing the weight on the balance's weighing platform and verifying the balance is weighing correctly. Always use the forceps provided to handle the calibration weights. Do NOT handle weights with your fingers. If you touch the calibration weight with your fingers the oil in your skin would change the weight's tolerance.
All calibration weights are not returnable. Once your order has been placed it CAN NOT be cancelled. Please carefully consider this prior to placing your order. The reason for this is these weights are custom manufactured. If you have questions please call 978-521-7095 before ordering.
Calibration Weights require a 7-10 business day lead time. If you can not work with this lead time please do not place the order since there is no rush service available. To perform proper calibration, weights need adequate time to establish and maintain a thermal equilibrium in the calibration laboratory room before any measurement can be made. All calibration weights are made to order and adjustments to the calibration weight are made on a polishing wheel that generates heat and requires time to reestablish thermal equilibrium before any calibration tolerance checks can be made on a balance. A quality calibration just can not be performed in a matter of a day. If someone tells you otherwise you should question their measurement practices and the quality of the calibration.
All calibration weights are not returnable. Once your order has been placed it CAN NOT be cancelled. Please carefully consider this prior to placing your order. The reason for this is these weights are custom manufactured. If you have questions please call 978-521-7095 before ordering.
Calibration Weights require a 7-10 business day lead time
Supplied in handcrafted wood case. Includes a compartment for a polycarbonate case which holds weights 500 grams and below. 1 kg weight is held in an individual polycarbonate case inside a felt-lined cutout
Weights
Included: 1 g, 2 x 2 g, 5 g, 10 g, 2 x 20 g, 50 g, 100 g, 2 x 200 g, 500 g, 1 kg
All
calibration weights are not returnable. Once
your order has been placed it CAN NOT be cancelled.
Please carefully consider this prior to placing your order.
The reason for this is these weights are custom manufactured
and are certified on the date they were made. In addition,
if you touch the calibration weight with your fingers
the oil in your skin would change the tolerance and we can
not take this chance if the weight was returned.
Traceable Certificate (Example of Certificate)
Traceable Certificate are available for any UltraClass, Class 1, or Class 2 weight or weight set. The "T" at the
end of the part number designates a Traceable Certificate will
be included with your weight(s). This
report identifies:
Name & address of the person that ordered weight(s)
Date of calibration
Serial number (Storage case has serial #. If you want weights themselves to have serial numbers laser marking is available at an additional cost of $50 per weight. If you want laser marking please call us before placing order.)
Tolerance Class of weight (i.e. Class 1, Class 2)
Nominal value
Conventional mass correction: "As found data" (not provided with new weights)
Conventional mass correction: "As left data"
Uncertainty of measurement process
Construction and density of weights
Statement of traceability to NIST
Use only one series of comparisons using a single standard
NIST test number
NVLAP Accredited Certificate (Example of Certificate)
NVLAP Accredited Certificate are available for any UltraClass, Class 1, or Class 2 weight or weight set. The "W" at the
end of the part number designates a NVLAP Certificate of Calibration will
be included with your weight(s). The NVLAP Certificate of Calibration
includes everything found in a Traceable Certificate listed above
along with the additional items below.
Identification of the balance used in the calibration – calibration due dates for equipment
Date the primary standards were last tested at NIST and the
NIST test number
Conventional mass value "As found data" (not provided with new weights)
Conventional mass value "As left data"
True mass value: (mass in a vacuum) "As found data" (not provided with new weights)
True mass value: (mass in a vacuum) "As left data"
Environmental conditions (temperature, barometric pressure, humidity) during test
Calibration procedures used
Pass/Fail result of magnetic testing
Helpful list of terms and definitions
Use only one series of comparisons using a single standard ASTM Classes 2, 3, 4, 5, 6
Multiple comparisons using a check standard for ASTM Classes 0 & 1 weights
Who do you feel needs a NVLAP Accredited Certificate
verses Report of Traceability?
If you are under ISO, FDA or other regulation we recommend you get a NVLAP Accredited Certificate. Also, anyone that plans to calculate uncertainty for their own
process would need the NVLAP Certificate.
If you have a balance or scale with the ability to read to a milligram or better it is always recommended you know the corrected value of the weight and this is only available with the NVLAP Certificate. Additional information to help you decide can be reviewed HERE.
We recently had a customer that ordered the Class 1 500g weight with Traceability Certificate and then determined he ordered the wrong certification and required the NVLAP Certificate and the cost for changing to NVLAP Accredited Certificate was $94 plus shipping both ways. The only way to get the NVLAP Accredited Certificate is sent the weight in for recertification and this is a costly an time consuming process. You need to fill out a calibration service order form along with
a statement of decontamination form. We feel with regulations always increasing just buy weights with NVLAP Certificates.
Recertification Service Weight values can change over time due to scratches, fingerprints,
wear and even corrosion resulting from atmospheric contaminants.
Regular checks on the accuracy of mass standards ensures the accuracy
of measurements. We have access to mass metrology lab providing
this service at a very competitive prices.
The rates vary depending upon the size of the weight (1 gram cost less than a 5kg weight) are listed below and subject to change.
Typical turn around time (excludes transit time) is 7 to 10 business
days upon receipt at the metrology lab. You
are responsible for both in and out bound freight and insurance
costs.
Single weights - 1g - $59, 5kg - $144
Weight sets depend upon the amount of weights in a set - 21 piece set 1mg - 100g - $894
Please call us for up to date pricing and the procedure involved in sending your weights in for recertification. A statement of decontamination form must be completed certifying the weight(s) are free of any radioactive, biohazards
or otherwise dangerous substances / gasses and are safe for human handling.
What does calibration of a laboratory weight entail?
All calibrations are accredited calibrations performed using weights by NIST weighing designs, where
all weights are compared against a weight standard. The mass comparators used for performing the calibration ascertain and measure differences to 10, 1,
and even 0.1 micrograms (one ten-millionth of a gram). The
value of the unknown weight is computed using a least sum squares
technique by the NIST mass code software. The software performs
statistical checks on the balance performance and the computed values
of the second standard. If the balance performance or computed
value of the second standard are found to be unacceptable the software
requires that the measurement be repeated. It is only when
the process standard deviation and computed value of the check standard
are acceptable that metrologist is confident in the value for the
customer's weight. All measurements in metrology laboratory,
including tolerance testing, use this Echelon I weighing technique.
The weighing designs are the same ones developed and used by NIST.
All measurement results are traceable to the International Prototype
Kilogram (IPK) through a NIST calibration of our primary standards.
Calibration technicians must wear appropriate static free clothing,
as well as gloves, hair nets and face masks, to reduce the possibility
of contamination (and changing the weight of the weights) from skin
oils, hairs, or airborne droplets. Calibration weights are
never touched directly by human hands.
What is True Mass Correction?
Basically, the only people who use "True Mass" are
calibration laboratories and other people who apply air buoyancy
corrections to the measurements. Conventional mass is what a weight would weigh at sea level at standard
temperature and pressure. Since most people use their weights in air and
don't have the equipment or desire to measure and calculate the air density
they have no need for the true mass values. NVLAP published NIST Handbook
150-2G requiring calibration certificates to reporting "true mass". If someone needs true mass they typically will know how to calculate it from the
Conventional mass.
What is Uncertainty?
Uncertainty is more than just the repeatability of the balance it is a
summation of all things which contribute to the error in the measurement
process. Uncertainty is the root sum square of balance deviation, repeatability on
the check standard, variability in the density of the standard, variability
in the density of the weight under test, variability of the temperature,
variability of the barometric pressure, variability of the humidity,
operator skill and the uncertainty of the standard used multiplied by two.
Construction and General Shape:
Troemner Calibration Weights 1 gram and larger consist of a body and a lifting knob. The lifting knob is specifically designed for use with forceps, tweezers or some other lifting device. Weight bottoms are slightly recessed to expose the smallest possible area to wear. Each weight is marked with its nominal value.
Weights 500 mg and lower are made of sheet metal and are one-piece construction with one side turned up to make them easy to handle with forceps. Depending on the class, these weights may or may not be marked with their nominal value.
(7-10 days lead time for all calibration weights and mass sets)
Surface Finish:
All surfaces are polished to a perfect, mirror-like finish and conform to specifications in ANSI/ASTM E617
Polycarbonate Cases for Individual Weights:
To safeguard your Troemner Alloy 8 Stainless Steel Precision Calibration Weights, attractive, durable, high quality, polycarbonate case is provided. A compartment for each weight as well as compartments for a brush, forceps and USB flash drive containing the calibration certificate is included.
Selecting The Right Weight:
Check you scale's manual or specification sheet to find the weight value required to calibrate your scale.
It is recommended that the weight selected to calibrate a balance and/or scale have a tolerance small enough as not to be detected by the balance and/or scale. Troemner recommends the tolerance of a weight selected for calibrating a balance and/or scale is no more than 1/3 of the readability or precision of the balance and/or scale being calibrated. If this cannot be achieved, it is suggested that a Class 1 Electronic Balance Calibration Weight with a NVLAP certificate be ordered which provides the actual mass value for the weight which reduces measurement uncertainty.
Electronic Balance Calibration Weights can also be used to check or verify the accuracy of your balance and/or scale between calibrations. It is recommended that the user check a balance and/or scale prior to each use. Keeping the weight at or near the balance and/or scale keeps the weight at the same temperature as the equipment.
Weights
Included: 1 g, 2 x 2 g, 5 g, 10 g, 2 x 20 g, 50 g, 100 g, 2 x 200 g, 500 g
All
calibration weights are not returnable. Once
your order has been placed it CAN NOT be cancelled.
Please carefully consider this prior to placing your order.
The reason for this is these weights are custom manufactured
and are certified on the date they were made. In addition,
if you touch the calibration weight with your fingers
the oil in your skin would change the tolerance and we can
not take this chance if the weight was returned.
All
calibration weights are not returnable. Once
your order has been placed it CAN NOT be cancelled.
Please carefully consider this prior to placing your order.
The reason for this is these weights are custom manufactured
and are certified on the date they were made. In addition,
if you touch the calibration weight with your fingers
the oil in your skin would change the tolerance and we can
not take this chance if the weight was returned.
Weights
Included: 1g, 2 x 2g, 5g, 10g, 2 x 20g, 50g, 100g
All
calibration weights are not returnable. Once
your order has been placed it CAN NOT be cancelled.
Please carefully consider this prior to placing your order.
The reason for this is these weights are custom manufactured
and are certified on the date they were made. In addition,
if you touch the calibration weight with your fingers
the oil in your skin would change the tolerance and we can
not take this chance if the weight was returned.
Weights
Included: 1mg, 2 x 2mg, 5mg, 10mg, 2 x 20mg, 50mg, 100mg,
2 x 200mg, 500mg, 1g, 2 x 2g, 5g, 10g, 2 x 20g, 50g, 100g
All
calibration weights are not returnable. Once
your order has been placed it CAN NOT be cancelled.
Please carefully consider this prior to placing your order.
The reason for this is these weights are custom manufactured
and are certified on the date they were made. In addition,
if you touch the calibration weight with your fingers
the oil in your skin would change the tolerance and we can
not take this chance if the weight was returned.
Weights
Included: 100 mg, 2 x 200 mg, 500 mg, 1 g, 2 x 2 g, 5 g, 10 g, 20 g
All
calibration weights are not returnable. Once
your order has been placed it CAN NOT be cancelled.
Please carefully consider this prior to placing your order.
The reason for this is these weights are custom manufactured
and are certified on the date they were made. In addition,
if you touch the calibration weight with your fingers
the oil in your skin would change the tolerance and we can
not take this chance if the weight was returned.
Weights
Included: 1 mg, 2 x 2 mg, 5 mg, 10 mg, 2 x 20 mg, 50 mg, 100 mg, 2 x 200 mg, 500 mg
All
calibration weights are not returnable. Once
your order has been placed it CAN NOT be cancelled.
Please carefully consider this prior to placing your order.
The reason for this is these weights are custom manufactured
and are certified on the date they were made. In addition,
if you touch the calibration weight with your fingers
the oil in your skin would change the tolerance and we can
not take this chance if the weight was returned.
What is the difference in tolerance between Class 1, Class 2 and other calibration specifications?
Metric
Weight Tolerances - all tolerances stated in milligram (mg)
American
Society of Testing & Measurement ASTM E617
International
Organization of Legal
Metrology Recommendation R111
Denomi-
nation
Metric
Class
1
mg
Class
2
mg
Class
3
mg
Class
4
mg
Class
5
mg
Class
6
mg
Class
7
mg
E1
mg
E2
mg
F1
mg
F2
mg
M1
mg
M2
mg
5
kg
12
25
50
100
250
500
1400
2.5
7.5
25
75
250
750
3
kg
7.5
15
30
60
150
300
1000
2
kg
5.0
10
20
40
100
200
750
1.0
3.0
10
30
100
300
1
kg
2.5
5.0
10
20
50
100
470
0.5
1.5
5
15
50
150
500
g
1.2
2.5
5.0
10
30
50
300
0.25
0.75
2.5
7.5
25
75
300
g
0.75
1.5
3.0
6.0
20
30
210
200
g
0.50
1.0
2.0
4.0
15
20
160
0.1
0.30
1.0
3.0
10
30
100
g
0.25
0.50
1.0
2.0
9
10
100
0.05
0.15
0.5
1.5
5
15
50
g
0.12
0.25
0.60
1.2
5.6
7
0.030
0.10
0.30
1.0
3.0
10
30
g
0.074
0.15
0.45
0.90
4.0
5
44
20
g
0.074
0.10
0.35
0.70
3.0
3
33
0.025
0.080
0.25
0.8
2.5
8
10
g
0.050
0.074
0.25
0.50
2.0
2
21
0.020
0.060
0.20
0.6
2
6
5
g
0.034
0.054
0.18
0.36
1.3
2
13
0.015
0.050
0.15
0.5
1.5
5
3g
0.034
0.054
0.15
0.30
0.95
2
9.4
2
g
0.034
0.054
0.13
0.26
0.75
2
7.0
0.012
0.040
0.12
0.4
1.2
4
1
g
0.034
0.054
0.10
0.20
0.50
2
4.5
0.010
0.030
0.10
0.3
1.0
3
500
mg
0.010
0.025
0.080
0.16
0.38
1
3.0
0.008
0.025
0.08
0.25
0.80
2.5
200
mg
0.010
0.025
0.060
0.12
0.26
1
1.8
0.006
0.020
0.06
0.20
0.6
2
100
mg
0.010
0.025
0.050
0.10
0.20
1
1.2
0.005
0.015
0.05
0.15
0.5
1.5
50
mg
0.010
0.014
0.042
0.085
0.16
0.5
0.88
0.004
0.012
0.04
0.12
0.4
20
mg
0.010
0.014
0.035
0.070
0.12
0.5
0.56
0.003
0.010
0.03
0.10
0.30
10
mg
0.010
0.014
0.030
0.060
0.10
0.5
0.4
0.002
0.008
0.025
0.08
0.25
5
mg
0.010
0.014
0.028
0.055
0.080
0.2
0.002
0.006
0.020
0.06
0.20
2
mg
0.010
0.014
0.025
0.050
0.060
0.2
0.002
0.006
0.020
0.06
0.20
1
mg
0.010
0.014
0.025
0.050
0.050
0.1
0.002
0.006
0.020
0.06
0.20
The
table above is a listing of the tolerances of various classes
of masses. The weight value can deviate above or below
the nominal value by the tolerance defined. To determine
the tolerance of a mass, look at the denomination or nominal
value of the weight and the appropriate class
you need.
All
calibration weights are not returnable. Once
your order has been placed it CAN NOT be cancelled.
Please carefully consider this prior to placing your order.
The reason for this is these weights are custom manufactured
and are certified on the date they were made. In addition,
if you touch the calibration weight with your fingers
the oil in your skin would change the tolerance and we can
not take this chance if the weight was returned.
Certificate Options
Traceable Certificate
The Traceable Certificate is designed for those laboratories and companies that require traceability, but do not need to meet any stringent regulatory requirements. The Traceable Certificate measurement process is based on a single standard and utilizes one series of comparisons The Traceable Certificate includes nominal value, mass correction, uncertainty and tolerance for each weight in addition to the basic customer information such as name, address, purchase order number, date of calibration, accuracy class, density and statement of traceability to NIST.
The NVLAP Accredited Certificate provides compliance in both measurement process and data reported to the customer to meet a variety of standards including NVLAP Handbook 150-2, ISO/IEC 9000, ISO/IEC 17025, FDA, GMP, GLP, DOD, ANSI/NCSL Z540-1, and nuclear requirements. The NIST administered National Voluntary Laboratory Accreditation Program (NVLAP) approves, through periodic audits, all processing and weighing procedures, as well as certificate format and content. Calibration procedures vary by tolerance class requested. For example, for higher accuracy classes such as Troemner Class 0 and 1. Troemner performs a multiple weighing procedure utilizing their secondary working standards to determine the mass of a customer's weight. Procedures and processes used to generate this multi-page certificate, as well as its format and content, are prescribed by NVLAP. Users held absolutely accountable for their weights should order weights with NVLAP certification.
Customer name & address
Date of calibration
Equipment and standards used in the calibration
Accuracy class
True mass value (mass in a vacuum)
"As found" mass correction (for recalibration) and "as left" mass corrections for each weight
Uncertainty of measurement process for each weight. Uncertainty to tolerance ratios are guaranteed.