DIFFERENTIAL PRESSURE FLOW METERS – DIAL TYPE

SERIES M12
Analog Dial Display (Mechanical)
Flow Rate Only

Threaded

Wafer

(Was Model 300, 301, 302), (Was Model 300W, 301W, 302W)

Meter Type
Differential Pressure Flow/Meter for fluids or gases

How It Works
Measures flow based on pressure differential created across a built-in nozzle

Features

Large 3-1/2” Analog Dial Display
Mechanical – requires no power
Factory calibrated for Liquid or Gas
Display Head can be mounted to read horizontally left or right of vertical piping or above or below of horizontal piping. (Below is ideal for steam applications.)

Applications*
*Always verify chemical compatibility with the body materials, the seals and all internal wetted parts.

All 3 body materials are suitable for:

Water, including Deionized (DI), Demineralized & Distilled Water, Steam, most Oils & Solvents, and many low viscosity fluids
Compressed Air, Oxygen, Carbon Dioxide and many other non-toxic compressed gases

Monel is suitable for:

Sea Water and Brackish Water
Up to 25% Nitric Acid
Other acids and alkalines

Sizes

1/4″ to 8″

Options and Application Notes

Options

EPR, Viton®, Teflon® Seals
350°F, 400 PSIG (120°F Max for Digital Meters)
LPM, SCFM, Nm³/H, Lbs/HR Scales
Factory Calibration for Stable Specific Gravities other than 1.0
Factory Calibration for Stable Viscosities under 500 cP
Non-Standard Flow Rates
Aluminum Housing with Plastic or Glass Crystal
4-20mA Output Signal
Saturated Steam Service (120 PSIG Max.)
Compressed Gas Service
Ammonia Service
Custom Scales (including Dual Scales)
Peak Flow Indicator Dial
Remote Readouts
Panel Mount Meter Case (1½” or smaller only)
1 or 2 Reed switches SPDT
Two Set Point Relays (High/Low)
Cleaning for Oxygen Service
24VDC Power Supply
NIST Calibration Certificates 4 to 200 GPM Full Scale up to Size 3″ (at time of order)
Expedited Shipping (please contact our Sales Dept.)
BSP Connections in Bronze or Stainless Steel

Application Notes

Saturated Steam Service: Acceptable when configured for Saturated Steam Service (Max 120 PSIG)
Potable Water: Not acceptable
Vacuum Service: Not acceptable
Gaseous Service: Acceptable when configured for Gases
Installation: 10 pipe diameters of straight pipe required Upstream, No requirements downstream. Keep medias from freezing at all times in meter. Do not subject meter to water hammer. These Digital Meters require 24VDC power. We recommend that they are installed by an experienced installer or electrician.
Corrosion: Before ordering, verify all materials of our flow meters are compatible with the service media(s), intermittently used cleaners, the environment, and cleaning processes in conjunction with the temperatures and pressures of the application(s) and future applications. John C. Ernst Co. does not make chemical compatibility recommendations. Compatibility is the responsibility of the user and/or specifying party.

Replacement Parts

Please contact our sales department

Alternate Meters

Series GPI-01, GPI-A1, GPI-G2
Series M12 (FLG)

ORDERING REQUIREMENTS FOR METERS

For Liquids Please Specify

Body Material: Bronze, 316SS, or Monel
Seals: Buna-N, Ethylene Propylene, Viton®, or Teflon®
Connection Size: 1/2″ to 8″
Flow Range: See Scale options
Flow Direction:
- Horizontal Left to Right
- Horizontal Right to Left
- Vertical Up mounted on Left or Right
- Vertical Down mount on Left or Right
Media: If other than Water
Pressure: Between 10 PSIG to 400 PSIG
Temperature: Between -80 to 350°F
Specific Gravity: At normal operating temperature (If under .95 S.G. or over 1.05 S.G.)
Viscosity: At normal operating temperature (If over 5 cP)

For Gases Please Specify

Body Material: Bronze, 316SS, or Monel
Seals: Buna-N, Ethylene Propylene, Viton®, or Teflon®
Connection Size: 1/4″ to 8″
Flow Range: See Scale options
Flow Direction:
- Horizontal Left to Right
- Horizontal Right to Left
- Vertical Up mounted on Left or Right
- Vertical Down mount on Left or Right
Gas: Name of gas
Pressure: Specify one specific or average pressure between 10 PSIG to 400 PSIG at meter inlet
Temperature: Specify one specific or average temperature between -80 to 350°F at meter inlet
Saturated Steam: Specify one specific or average pressure between 10 PSIG to 120 PSIG at meter inlet

Pressure Drop Chart

Meter Head Mounting Options

Detailed Specifications

Specifications
Dial Display Meters
DISPLAY INFO
Flow Measurements	Rate of Flow
Display Size	3-5/16” Dia.
ACCURACY (Full Scale)	±3%
REPEATABILITY (Full Scale)	±1%
PRESSURE
Standard Rating	180 PSIG (12.4 Bar)
Optional Maximum Rating	400 PSIG (27.5 Bar)
Minimum Required	10 PSIG (0.69 Bar)
Standard Calibration for	100 PSIG (6.9 Bar)
TEMPERATURE
Standard Rating	212°F (100°C)
Optional Maximum Rating	350°F (176°C)
Minimum Rating	-30°F (-34°C)
Standard Calibration for	80°F (26°C)
PRESSURE DROP
Bronze Meters at Full Scale	5 PSIG (0.34 Bar)
High Pressure Meters (400 PSIG)	7 PSIG (0.48 Bar)
Stainless & Monel Meters at Full Scale	7 PSIG (0.48 Bar)
VISCOSITY
Standard Factory Calibration	< 5cps
Optional Factory Calibration Required	Up to 500cps
SPECIFIC GRAVITY
Standard Factory Calibration	.95 - 1.05 S.G.
Optional Factory Calibration Required	< 0.95 S.G. or > 1.05 S.G.
STRAIGHT PIPE REQUIREMENTS
Upstream (Pipe Diameters)	10
Downstream (Pipe Diameters)	0

Detailed Materials Of Construction

	Materials Of Construction
	Bronze	316 Stainless Steel	Monel
WETTED MATERIALS (Standard)
Body	Bronze	316 Stainless Steel	Monel
Seals	Buna-N	Buna-N	Buna-N
Bellows	Bronze	316 Stainless Steel	Monel
Cell Caps	Ryton®	Ryton®	Ryton®
WETTED MATERIALS (Optional)
Seals	Viton®, EPR, TFE	Viton®, EPR, TFE	Viton®, EPR, TFE
Bellows	-	-	Inconel®
Cell Caps	Bronze, SS	Bronze, SS	Monel
NON-WETTED PARTS (Standard)
Housing	Super ABS UV Stabilized	Super ABS UV Stabilized	Super ABS UV Stabilized
Crystal	Polycarbonate	Polycarbonate	Polycarbonate
Gear Movement	Bronze	Bronze	Bronze
NON-WETTED PARTS (Optional)
Housing	Epoxy Coated Aluminum	Epoxy Coated Aluminum	Epoxy Coated Aluminum
Crystal	Glass (for Aluminum Housing)	Glass (for Aluminum Housing)	Glass (for Aluminum Housing)
Gear Movement	-	Stainless Steel	Stainless Steel

Detailed Standard Max. Flow Rate Scale GPM*

Size	Standard Max. Flow Rate Scale GPM*	Conn. to Conn. Length		Weight
		FNPT	Wafer	FNPT	Wafer
1/4”	2, 3, 4	3.06”		4 Lbs
1/2” Low Flow	4, 6, 10, 15, 20, 30, 40, 60, 100 GPH	3.06”		4 Lbs
1/2”	2, 3, 4, 6, 10	3.06”	1.12”	4 Lbs	4 Lbs
3/4”	6, 10, 15, 20	3.06”	1.12”	4 Lbs	5 Lbs
1”	15, 20, 30, 40	3.06”	1.12”	4 Lbs	5 Lbs
1-1/2”	30, 40, 60, 100	3.06”	1.12”	5 Lbs	6 Lbs
2”	40, 60, 100, 150, 200	3.19”	1.12”	7 Lbs	7 Lbs
2-1/2”	60, 100, 150, 200		1.12”		8 Lbs
3”	200, 300, 400, 500	4.19”	1.12”	12 Lbs	9 Lbs
4”	300, 400, 500, 800		1.12”		12 Lbs
5”	300, 400, 500, 800		1.12”		14 Lbs
6”	600, 800, 1000, 2000		1.12”		16 Lbs
8”	600, 1000, 2000, 3000		1.12”		24 Lbs

*Optional Flow Rate Scales:
GPH (Liquids), LPH (Liquids), LPM (Liquids), CC/M (Liquids), SCFH (Gases), SCFM (Gases), Nm³/h (Gases), Lbs/Hr (Steam)
Non-Standard Flow Rate Scales are available in up to 3 connection sizes below the standard scale of the connection size.
Please contact our Sales Dept. for pricing and to order.

Detailed Flow Rate Scales

Low Flow Range Scales

		Standard Low-Flow Range Scales
		Liquid			Gases
Scale	Size	GPH	LPH	CC/M	SCFH	Nm³/h
1	1/2”	.5 - 4	2 - 15	30 - 200	5 - 40	.15 - 1
2	1/2”	.5 - 6	3 - 20	40 - 300	5 - 60	.3 - 2
3	1/2”	1.5 - 10	5 - 40	50 - 400	15 - 100	.4 - 3
4	1/2”	2 - 15	5 - 60	50 - 600	20 - 150	.5 - 4
5	1/2”	3 - 20	10 - 80	150 - 1000	30 - 200	.5 - 6
6	1/2”	4 - 30	15 - 120	300 - 2000	40 - 300	1 - 8
7	1/2”	5 - 40	20 - 150	400 - 3000	50 - 400	1.5 - 10
8	1/2”	5 - 60	30 - 240	500 - 4000	-	-
9	1/2”	15 - 100	50 - 400	500 - 6000	-	-

Standard Flow Range Scales

		Standard Flow Range Scales
		Liquid		Gases		Steam
Scale	Size	GPM	LPM	SCFM	Nm³/h	Lbs/Hr
A	1/2"	.3 - 2	1 - 8	1.5 - 10	2 - 15	5 - 40
B	1/2"	.4 - 3	1.5 – 10	3 - 20	4 - 30	5 - 60
C	1/2"	.5 - 4	2.0 – 15	4 - 30	6 - 50	10 - 80
D	1/2"	.5 - 6	3 - 25	5 - 40	10 - 80	15 - 120
E	1/2"	1.5 - 10	5 - 40	5 - 60	15 - 100	30 - 200
D	3/4"	.5 - 6	3 - 25	5 - 40	10 - 80	15 - 120
E	3/4"	1.5 - 10	5 - 40	5 - 60	15 - 100	30 - 200
F	3/4"	2 - 15	5 - 60	20 - 150	30 - 200	40 - 300
G	3/4"	3 - 20	10 - 80	30 - 200	40 - 300	50 - 400
F	1"	2 - 15	5 - 60	20 - 150	30 - 200	40 - 300
G	1"	3 - 20	10 - 80	30 - 200	40 - 300	50 - 400
H	1"	4 - 30	15 - 120	40 - 300	60 - 500	50 - 600
I	1"	5 - 40	20 - 150	50 - 400	50 - 600	100 - 800
H	1½"	4 - 30	15 - 120	40 - 300	60 - 500	50 - 600
I	1½"	5 - 40	20 - 150	50 - 400	50 - 600	100 - 800
J	1½"	5 - 60	30 - 240	50 - 600	150 - 1000	150 - 1000
K	1½"	15 - 100	50 - 400	100 - 800	150 - 1200	300 - 2000
I	2"	5 - 40	20 - 150	50 - 400	50 - 600	100 - 800
J	2"	5 - 60	30 - 240	50 - 600	150 - 1000	150 - 1000
K	2"	15 - 100	50 - 400	100 - 800	150 - 1200	300 - 2000
L	2"	20 - 150	50 - 600	150 - 1000	200 - 1500	400 - 3000
M	2"	30 - 200	100 - 800	150 - 1200	300 - 2000	500 - 4000
J	2½"	5 - 60	30 - 240	50 - 600	150 - 1000	150 - 1000
K	2½"	15 - 100	50 - 400	100 - 800	150 - 1200	300 - 2000
L	2½"	20 - 150	50 - 600	150 - 1000	200 - 1500	400 - 3000
M	2½"	30 - 200	100 - 800	150 - 1200	300 - 2000	500 - 4000
M	3"	30 - 200	100 - 800	150 - 1000	200 - 1500	500 - 4000
N	3"	40 - 300	150 - 1000	300 - 2000	400 - 3000	500 - 6000
O	3"	50 - 400	200 - 1500	400 - 3000	600 - 5000	1000 - 8000
P	3"	50 - 500	300 - 2000	500 - 4000	500 - 6000	1500 - 10000
Scale	Size	GPM	LPM	SCFM	Nm³/m	Lbs/Hr
N	4"	40 - 300	150 - 1000	200 - 1500	6 - 50	500 - 6000
O	4"	50 - 400	200 - 1500	400 - 3000	15 - 100	1000 - 8000
Q	4"	50 - 600	300 - 2400	600 - 5000	20 - 150	1500 - 10000
R	4"	100 - 800	400 - 3000	500 - 6000	30 - 200	2000 - 15000
N	5"	40 - 300	150 - 1000	200 - 1500	6 - 50	500 - 6000
O	5"	50 - 400	200 - 1500	400 - 3000	15 - 100	1000 - 8000
Q	5"	50 - 600	300 - 2400	600 - 5000	20 - 150	1500 - 10000
R	5"	100 - 800	400 - 3000	500 - 6000	30 - 200	2000 - 15000
Q	6"	50 - 600	300 - 2400	400 - 3000	15 - 100	1500 - 10000
R	6"	100 - 800	400 - 3000	600 - 5000	20 - 150	2000 - 15000
S	6"	150 - 1000	500 - 4000	1000 - 8000	30 - 250	3000 - 20000
T	6"	300 - 2000	1000 - 8000	2000 - 15000	50 - 400	5000 - 40000
Q	8"	50 - 600	300 - 2400	500 - 5000	15 - 150	1500 - 10000
S	8"	150 - 1000	500 - 4000	1000 - 8000	30 - 250	3000 - 20000
T	8"	300 - 2000	1000 - 8000	2000 - 15000	50 - 400	5000 - 40000
U	8"	400 - 3000	1500 - 12000	3000 - 20000	50 - 600	5000 - 60000

Note: Non-Standard Flow Rates are available in up to 3 connection sizes below the standard scale of the connection size required. Please contact our Sales Dept. for pricing and to order.

Model Number Matrix