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An instrument designed to measure, memorise and display the quantity of fuel gas (volume or mass) that has passed it.


Legal Tolerences

Minimum Measured Quantity
(MMQ)

Maximum permissible error (Emin)

Verification

Inservice Inspection

MMQ < 0.1 litre

+4ml
-4ml
+8ml
-4ml

0.1 litre  ≤ MMQ < 0.2 litre

+4%
-4%

+8%
-4%

0.2 litre  ≤ MMQ < 0.4 litre

+8ml
-8ml

+16ml
-8ml

0.4 litre  ≤ MMQ < 1litre

+2%
-2%
+4%
-2%

1 litre  ≤ MMQ < 2 litre

+20ml
-20ml
+40ml
-20ml
2 litre  ≤ MMQ +1%
-1%
+2%
-1%

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