In the CMCs uncertainty statements, the notation Q[a, b] stands for the root-sum-square of the terms between brackets: Q[a, b] = [a 2 + b 2]1/2
Unless otherwise stated the expanded uncertainties given below correspond to k = 2 (at a 95 % level of confidence)
Bulgaria, BIM (Bulgarian Institute of Metrology)
High voltage and current , High DC voltage: ratios : 1.00E-5 to 1
High voltage resistive divider, DC high voltage probe
Relative expanded uncertainty : 2.0E-4
Comparison with reference divider
Input voltage : -100 kV to 200 kV
Approved on 06 August 2013
Institute service identifier : 91
Items for disseminating ITS-90 and PLTS 2000 , Temperature : 100 °C to 250 °C
Thermistors and other resistive thermometer
Absolute expanded uncertainty : 2.0E1 mK
Comparison
Stirred liquid bath : silicon oil
Approved on 03 November 2009
Institute service identifier : BIM/4.3
Items for disseminating ITS-90 and PLTS 2000 , Temperature : 100 °C to 250 °C
Liquid-in-glass thermometer
Absolute expanded uncertainty : 2.5E1 mK
Comparison
Stirred liquid bath : silicon oil
Approved on 03 November 2009
Institute service identifier : BIM/7.4
Hygrometers , Humidity : 10 %rh to 30 %rh
Other hygrometer
Absolute expanded uncertainty : 1.4 %rh
Comparison in a climatic chamber
Air temperature : 20 °C to 50 °C
Approved on 17 August 2017
Institute service identifier : BIM/3.3.1
DC resistance , DC resistance meters: low values : 1.00E-4 Ω to 1 Ω
Micro-ohmmeter, multimeter: R
Relative expanded uncertainty : 1.2E2 µΩ/Ω to 3 µΩ/Ω
{"row_1":{"col_1":"","col_2":"Expanded uncertainty"},"row_2":{"col_1":"0.0001 ohm","col_2":"120"},"row_3":{"col_1":"0.001 ohm","col_2":"70"},"row_4":{"col_1":"0.01 ohm","col_2":"70"},"row_5":{"col_1":"0.1 ohm","col_2":"70"},"row_6":{"col_1":"1 ohm","col_2":"3.0"}}
The expanded uncertainties given in this table are expressed in µΩ/Ω
Direct measurement
R : decade values
Approved on 06 August 2013
Institute service identifier : 80
Impedance (up to the MHz range) , Capacitance for dielectric capacitors : 0.01 µF to 1 µF
Fixed capacitor
Relative expanded uncertainty : 2.0E1 µF/F to 5.0E1 µF/F
{"row_1":{"col_1":"","col_2":"Expanded uncertainty in µF/F"},"row_2":{"col_1":"10 nF to 100 nF","col_2":"20 to 30"},"row_3":{"col_1":"200 nF to 1 µF","col_2":"50"}}
Comparison with capacitance bridge
Frequency : 1 kHz
Uncertainty is not varying linearly within the range.
Approved on 07 February 2019
Institute service identifier : 25
AC power , AC power and energy: three phase, active power : 0 W to 1.44E5 W
Power meter, power converter, power comparator, wattmeter, power calibrator
Relative expanded uncertainty : 1.6E1 µW (VA)-1 to 1.7E2 µW (VA)-1
{"row_1":{"col_1":"","col_2":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_3":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_4":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_5":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_6":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_7":"For calibration of power calibrator"},"row_2":{"col_1":"Power factor","col_2":"4-wire measuring mode 10 V to 240 V 0.002 A to 0.05 A","col_3":"4-wire measuring mode 10 V to 240 V 0.051 A to 100 A","col_4":"4-wire measuring mode 241 V to 480 V 0.002 A to 0.05 A","col_5":"4-wire measuring mode 241 V to 480 V 0.051 A to 100 A","col_6":"3-wire measuring mode 10 V to 480 V 0.002 A to 100 A","col_7":"4-wire and 3 wire measuring mode 10 V to 480 V 0.002 A to 100 A"},"row_3":{"col_1":"1 to 0.8 inductive or capacitive","col_2":"20","col_3":"16","col_4":"40","col_5":"30","col_6":"140","col_7":"170"},"row_4":{"col_1":"0.5 inductive or capacitive","col_2":"30","col_3":"25","col_4":"60","col_5":"50","col_6":"140","col_7":"170"}}
The expanded uncertainties given in this table are expressed in µW/VA and µWs/VAs, µvar/VA and µvars/VAs, and µVA/VA
Direct comparison
Voltage : 10 V to 480 V
Frequency : 46 Hz to 65 Hz
Power factor : 1 to 0 inductive or capacitive
Current : 0.002 A to 100 A
Approved on 06 August 2013
Institute service identifier : 87
Matrix or material Dissemination range of measurement capability Range of certified values in reference materials
pH in Absolute expanded uncertainty in pH in Absolute expanded uncertainty in
aqueous pH buffer solution 6.7 to 7.6 4.0E-3 6.7 to 7.6 4.0E-3
  • Mechanism for measurement service delivery : Calibration services, value assignment of CRMs - CRM NCM 5.305 (pH 6.865) and CRM NCM 5.306 (pH 7.413); value assignment for proficiency testing scheme samples
  • Temperature range for calibration service: 20 °C to 40 °C, values given for 25 ºC. Declared uncertainties do not include the uncertainty contribution due to the Bates-Guggenheim convention (~ 0.010, k = 2)
  • Approved on 06 December 2011
  • Institute service identifier : 1.6.b-1
Hygrometers , Humidity : 30 %rh to 50 %rh
Other hygrometer
Absolute expanded uncertainty : 1.8 %rh
Comparison in a climatic chamber
Air temperature : 1 °C to 20 °C
Approved on 17 August 2017
Institute service identifier : BIM/3.3.1
Items for disseminating ITS-90 and PLTS 2000 , Temperature : 250 °C to 650 °C
IPRT
Absolute expanded uncertainty : 0.1 °C to 0.6 °C
Comparison
Furnace : metal block
Approved on 03 November 2009
Institute service identifier : BIM/3.4
DC resistance , DC resistance standards and sources: high values : 1.00E7 Ω to 1.00E9 Ω
Fixed resistor: R
Relative expanded uncertainty : 3.2 µΩ/Ω to 1.1E2 µΩ/Ω
{"row_1":{"col_1":"","col_2":"Expanded uncertainty"},"row_2":{"col_1":"10 Mohm","col_2":"3.2"},"row_3":{"col_1":"100 Mohm","col_2":"50"},"row_4":{"col_1":"1 Gohm","col_2":"110"}}
The expanded uncertainties given in this table are expressed in µΩ/Ω
Comparison by means of automated high resistance bridge
R : decade values
Measurements only at 23 °C in air bath
Approved on 06 August 2013
Institute service identifier : 75
Hygrometers , Humidity : 50 %rh to 90 %rh
Relative humidity sensors
Absolute expanded uncertainty : 2 %rh
Comparison in a climatic chamber
Air temperature : 20 °C to 50 °C
Approved on 17 August 2017
Institute service identifier : BIM/3.3.1
DC resistance , DC resistance standards and sources: multiple ranges : 1 Ω to 1.00E8 Ω
Multifunction calibrator: R
Relative expanded uncertainty : 1 µΩ/Ω to 5.5E1 µΩ/Ω
{"row_1":{"col_1":"","col_2":"Expanded uncertainty"},"row_2":{"col_1":"1 ohm","col_2":"1"},"row_3":{"col_1":"1.9 ohm","col_2":"1"},"row_4":{"col_1":"10 ohm","col_2":"1"},"row_5":{"col_1":"19 ohm","col_2":"1"},"row_6":{"col_1":"100 ohm","col_2":"1"},"row_7":{"col_1":"190 ohm","col_2":"1"},"row_8":{"col_1":"1 kohm","col_2":"1.5"},"row_9":{"col_1":"1.9 ohm","col_2":"1.5"},"row_10":{"col_1":"10 kohm","col_2":"2.1"},"row_11":{"col_1":"19 kohm","col_2":"2.1"},"row_12":{"col_1":"100 kohm","col_2":"2.4"},"row_13":{"col_1":"190 kohm","col_2":"2.4"},"row_14":{"col_1":"1 Mohm","col_2":"4.5"},"row_15":{"col_1":"19 Mohm","col_2":"4.5"},"row_16":{"col_1":"10 Mohm","col_2":"6.0"},"row_17":{"col_1":"19 Mohm","col_2":"6.0"},"row_18":{"col_1":"100 Mohm","col_2":"55"}}
The expanded uncertainties given in this table are expressed in µΩ/Ω
Comparison by means of current comparator bridge and automated high resistance bridge
R : decade values and divisible by 1.9
Approved on 06 August 2013
Institute service identifier : 79
DC resistance , DC resistance standards and sources: standards for high current : 10 mΩ
DC shunt
Relative expanded uncertainty : 2.6E1 µΩ/Ω
Indirect measurement with current calibrator and voltmeter
Maximum current : 10 A
Measurements only at 23 °C in oil or air bath
Approved on 06 August 2013
Institute service identifier : 78
AC power , AC power and energy: three phase, reactive power : 0 var to 1.44E5 var
Power meter, power converter, power comparator
Relative expanded uncertainty : 1.6E1 µvar (VA)-1 to 1.4E2 µvar (VA)-1
{"row_1":{"col_1":"","col_2":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_3":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_4":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_5":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_6":"For calibration of power meter, power converter, power comparator, wattmeter and energy meter","col_7":"For calibration of power calibrator"},"row_2":{"col_1":"Power factor","col_2":"4-wire measuring mode 10 V to 240 V 0.002 A to 0.05 A","col_3":"4-wire measuring mode 10 V to 240 V 0.051 A to 100 A","col_4":"4-wire measuring mode 241 V to 480 V 0.002 A to 0.05 A","col_5":"4-wire measuring mode 241 V to 480 V 0.051 A to 100 A","col_6":"3-wire measuring mode 10 V to 480 V 0.002 A to 100 A","col_7":"4-wire and 3 wire measuring mode 10 V to 480 V 0.002 A to 100 A"},"row_3":{"col_1":"1 to 0.8 inductive or capacitive","col_2":"20","col_3":"16","col_4":"40","col_5":"30","col_6":"140","col_7":"170"},"row_4":{"col_1":"0.5 inductive or capacitive","col_2":"30","col_3":"25","col_4":"60","col_5":"50","col_6":"140","col_7":"170"}}
The expanded uncertainties given in this table are expressed in µW/VA and µWs/VAs, µvar/VA and µvars/VAs, and µVA/VA
Direct comparison
Voltage : 10 V to 480 V
Frequency : 46 Hz to 65 Hz
Power factor : 1 to 0 inductive or capacitive
Current : 0.002 A to 100 A
Approved on 06 August 2013
Institute service identifier : 88
Items for defining ITS-90 , Temperature : 234.3156 °C
Capsule-type SPRT
Absolute expanded uncertainty : 0.5 mK
Calibration at mercury triple point
Mercury apparatus
Approved on 27 March 2014
Institute service identifier : BIM/2.1
Impedance (up to the MHz range) , Inductance: self inductance, low values : 0.01 mH to 1 mH
Fixed inductor
Relative expanded uncertainty : 2.0E-2 H/H to 3.0E-4 H/H
Comparison with inductance bridge
Frequency : 1 kHz
Uncertainty is not varying linearly within the range
Approved on 06 August 2013
Institute service identifier : 26
DC current (up to 100 A) , DC current meters: intermediate values : 1.00E-4 A to 2 A
Multimeter, multifunction transfer standard
Relative expanded uncertainty : 8 µA/A to 5.3E1 µA/A
{"row_1":{"col_1":"","col_2":"Expanded uncertainty"},"row_2":{"col_1":"100 µA to 200 µA","col_2":"8"},"row_3":{"col_1":"200 µA to 2 mA","col_2":"13 to 11"},"row_4":{"col_1":"2 mA to 20 mA","col_2":"13 to 8"},"row_5":{"col_1":"20 mA to 200 mA","col_2":"16 to 10"},"row_6":{"col_1":"200 mA to 2 A","col_2":"25 to 53"}}
The expanded uncertainties given in this table are expressed in µA/A
Direct measurement with calibrator
Approved on 06 August 2013
Institute service identifier : 16
Hygrometers , Humidity : 50 %rh to 90 %rh
Other hygrometer
Absolute expanded uncertainty : 2.2 %rh
Comparison in a climatic chamber
Air temperature : 1 °C to 20 °C
Approved on 17 August 2017
Institute service identifier : BIM/3.3.1
AC current , AC current: AC/DC transfer difference : 2 A to 10 A
AC-DC transfer standard plus shunt
Relative expanded uncertainty : 6.4E1 µA/A to 1.5E2 µA/A
{"row_1":{"col_1":"","col_2":"55 Hz","col_3":"300 Hz","col_4":"1 kHz","col_5":"5 kHz","col_6":"20 kHz"},"row_2":{"col_1":"2.5 mA","col_2":"41","col_3":"40","col_4":"47","col_5":"75","col_6":"-"},"row_3":{"col_1":"5 mA","col_2":"30","col_3":"28","col_4":"27","col_5":"50","col_6":"-"},"row_4":{"col_1":"10 mA","col_2":"25","col_3":"26","col_4":"26","col_5":"49","col_6":"-"},"row_5":{"col_1":"20 mA","col_2":"27","col_3":"30","col_4":"32","col_5":"47","col_6":"-"},"row_6":{"col_1":"30 mA","col_2":"35","col_3":"36","col_4":"36","col_5":"67","col_6":"-"},"row_7":{"col_1":"50 mA","col_2":"39","col_3":"36","col_4":"39","col_5":"75","col_6":"-"},"row_8":{"col_1":"100 mA","col_2":"43","col_3":"44","col_4":"45","col_5":"81","col_6":"-"},"row_9":{"col_1":"0.2 A","col_2":"48","col_3":"48","col_4":"49","col_5":"93","col_6":"-"},"row_10":{"col_1":"0.3 A","col_2":"53","col_3":"54","col_4":"53","col_5":"100","col_6":"-"},"row_11":{"col_1":"0.5 A","col_2":"56","col_3":"56","col_4":"56","col_5":"110","col_6":"-"},"row_12":{"col_1":"1 A","col_2":"59","col_3":"59","col_4":"61","col_5":"120","col_6":"-"},"row_13":{"col_1":"2 A","col_2":"65","col_3":"64","col_4":"66","col_5":"120","col_6":"120"},"row_14":{"col_1":"3 A","col_2":"67","col_3":"68","col_4":"69","col_5":"130","col_6":"130"},"row_15":{"col_1":"5 A","col_2":"69","col_3":"69","col_4":"69","col_5":"140","col_6":"150"},"row_16":{"col_1":"10 A","col_2":"72","col_3":"72","col_4":"72","col_5":"140","col_6":"140"}}
The expanded uncertainties given in this table are expressed in µA/A.
Comparison
Frequency : 55 Hz to 20 kHz
Approved on 06 August 2013
Institute service identifier : 48

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