The Measuring Instruments Regulations 2016

[F1 CHAPTER II E+W+S Automatic Catchweighers

Textual Amendments

F1 Schs. 1A-1K inserted (E.W.S.) (31.12.2020) by The Product Safety and Metrology etc. (Amendment etc.) (EU Exit) Regulations 2019 (S.I. 2019/696), reg. 1, Sch. 27 para. 49 (with Sch. 27 para. 50(a)) (as amended by S.I. 2020/676, regs. 1(1), 2); 2020 c. 1, Sch. 5 para. 1(1)

1.   These categories are divided into four accuracy classes: E+W+S

Y(I), Y(II), Y(a) & Y(b)

which shall be specified by the manufacturer.

MPE E+W+S

2.1.   MPE Category Y instruments E+W+S

Table 1

Net Load (m) in verification scale intervals (e)				Maximum permissible mean error	Maximum permissible error
Y(I)	Y(II)	Y(a)	Y(b)	Static	Automatic
0 < m ≤ 50,000	0 < m ≤ 5,000	0 < m ≤ 500	0 < m ≤ 50	± 0.5 e	± 1 e
50,000 < m ≤ 200,000	5,000 < m ≤ 20,000	500 < m ≤ 2,000	50 < m ≤ 200	± 1.0 e	± 1.5 e
200,000 < m	20,000 < m ≤ 100,000	2,000 < m ≤ 10,000	200 < m ≤ 1,000	± 1.5	± 2 e

Verification scale interval — single interval instruments E+W+S

Table 2

Accuracy classes		Verification scale interval	Number of verification scale intervalsn = Max/e
			Minimum	Maximum
			Minimum	Maximum
XI	Y(I)	0.001 g ≤ e	50,000
XII	Y(II)	0.001 g ≤ e ≤ 0.05 g	100	100,000
		0.1 g ≤ e	5,000	100,000
XIII	Y(a)	0.1 g ≤ e ≤ 2 g	100	10,000
		5 g ≤ e	500	10,000
XIIII	Y(b)	5 g ≤ e	100	1,000

Verification scale interval — multi-interval instruments E+W+S

Table 3

1 For i = r the corresponding column of Table 2 applies with e replaced by er.
Verification scale interval		Number of verification scale intervalsn = Max/e
		Minimum value1 n = Maxi /e(i+1) For i = r the corresponding column of Table 2 applies with e replaced by er.	Maximum value n = Maxi /ei
Y(I)	0.001 g ≤ ei	50,000
Y(II)	0.001 g ≤ ei≤ 0.05 g	5,000	100,000
	0.1 g ≤ ei	5,000	100,000
Y(a)	0.1 g ≤ ei	500	10,000
Y(b)	5 g ≤ ei	50	1 000

Where:

• i =  1, 2, … r

• i =  partial weighing range

• r =  total number of partial ranges

Measurement Range E+W+S

3.   In specifying the measurement range for class Y instruments the manufacturer shall take account that the minimum capacity shall not be less than:

class Y(I)	:	100 e
class Y(II)	:	20 e for 0.001 g ≤ e ≤ 0.05 g, and 50 e for 0.1 g ≤ e
class Y(a)	:	20 e
class Y(b)	:	10 e
Scales used for grading, e.g. postal scales and garbage weighers	:	5 e

Dynamic Setting E+W+S

4.1.   The dynamic setting facility shall operate within a load range specified by the manufacturer. E+W+S

4.2.   When fitted, a dynamic setting facility that compensates for the dynamic effects of the load in motion shall be inhibited from operating outside the load range, and shall be capable of being secured. E+W+S

Performance Under Influence Factors And Electromagnetic Disturbances E+W+S

5.1.   The MPEs due to influence factors are: E+W+S

5.1.1.   For category Y instruments E+W+S

• — For each load in automatic operation; as specified in Table 1,

• — For static weighing in non-automatic operation; as specified in Table 1.

5.1.2.   The critical change value due to a disturbance is one verification scale interval. E+W+S

5.2.   Temperature range: E+W+S

• — For class Y(I) the minimum range is 5 °C,

• — For class Y(II) the minimum range is 15 °C.]