Sec. 500.6. Registration of meters

(a) Displacement type.

The registration on the meter dial shall indicate the quantity recorded to be not less than 98.5 percent nor more than 101.5 percent of the water actually passed through the meter while it is being tested at any rate of flow within the limits specified herein under “normal test flow limits”. At the “minimum test flow” rate to the lowest normal test flow rate as set forth in the following table, the meter shall register not less than 95 percent and not more than 101 percent of the water that actually passes through it. The meter shall show proper sensitivity when tested at the rate of flow set forth under “minimum test flow” as provided in section 500.5 of this Part.

Size (inches)	Normal test flow limits (gallons per minute)	Minimum test flow (gallons per minute)
½	1 to 15	¼
½ × ¾	1 to 15	¼
⅝	1 to 20	¼
⅝ × ¾	1 to 20	¼
¾	2 to 30	½
1	3 to 50	¾
1 ½	5 to 100	1½
2	8 to 160	2
3	16 to 315	4
4	28 to 500	7
6	48 to 1,000	12

(b) Current type.

The registration on the meter dial shall indicate the quantity recorded to be not less than 98 percent nor more than 102 percent of the water actually passed through the meter while it is being tested at any rate of flow within the limits specified herein under “normal test flow limits”. The meter shall show proper sensitivity when tested at the rate of flow set forth under “minimum test flow” as provided in section 500.5 of this Part.

Size (inches)	Normal test flow limits (gallons per minute)	Minimum test flow (gallons per minute)
1 ½	12 to 100	1½
2	35 to 100	30
3	40 to 250	35
4	50 to 500	45
5	75 to 90	70
6	90 to 1,200	85
8	100 to 1,500	90
10	125 to 2,000	110
12	150 to 2,800	140

(c) Compound type.

(1) The registration on the meter dial shall indicate the quantity recorded to be not less than 97 percent nor more than 103 percent of the water actually passed through the meter while it is being tested at any rate of flow within the limits specified under “normal test flow limits”, except in the registration of flows within the “changeover” from by-pass meter to mainline meter. The registration at these rates of flow shall be not less than 90 percent and not more than 103 percent. The difference in the rate of flow at the beginning and at the end of the “changeover” shall not exceed the figures given in the following table:

Size (inches)	Gallons per minute
1 ½	20
2	20
3	30
4	30
6	40
8	75
10	100
12	620

(2) The beginning of the “changeover” is when the accuracy of registration falls below 97 percent, due to the automatic valve mechanism, and the end of the “changeover” is when the accuracy of registration again reaches 97 percent.

(3) The meter shall show proper sensitivity when tested at the rate of flow set forth under “minimum test flow” as provided in section 500.5 of this Part.

Size, main meter (inches)	Normal test flow limits (gallons per minute)		Minimum test flow (gallons per minute)
1 ½	2 to	100	½
2	2 to	160	½
3	4 to	320	1
4	6 to	500	1½
6	10 to	1,000	3
8	16 to	1,600	4
10	32 to	2,300	8
12	32 to	3,100	14

(d) Fire-service type.

(1) Registration on the meter dials shall indicate the quantity recorded to be not less than 97 percent nor more than 103 percent of the water actually passed through the meter while it is being tested at any rate of flow within the limits specified under “normal test flow limits”, except in the registration of flows within the “changeover” from by-pass meter to the mainline meter. The registration at these rates of flow shall be not less than 85 percent. The difference in the rate of flow at the beginning and at the end of the “changeover” shall not exceed the figures given in the following table:

Size (inches)	Gallons per minute
3	40
4	60
6	130
8	210
10	300
12	620

(2) The beginning of the “changeover” is when the accuracy of registration falls below 97 percent due to the automatic valve mechanism, and the end of the “changeover” is when the accuracy of registration again reaches 97 percent.

(3) The meter shall show proper sensitivity when tested at the rate of flow under “minimum test flow” as provided in section 500.5 of this Part.

Size (inches)	Normal test flow limits (gallons per minute)	Minimum test flow (gallons per minute)
3	8 to 400	2
4	8 to 700	2
6	16 to 1,600	4
8	28 to 2,800	7
10	48 to 4,400	12
12	48 to 6,400	12