Dwyer MFS - Manual (Page 7)

Maintenance and repairs Series MFS
Technical changes reserved 7 08/2011
7 Maintenance and repairs
The flow sensor is maintenance-free and cannot be repaired by the user. In the unlikely event of a defect, the
device has to be returned to the manufacturer for repair work.
8 Decommissioning and disposal
ª Never remove a flow sensor from a system under pressure.
ª Remove all the electrical connectors and disassemble the flow sensor.
ª The flow sensor consists of various materials. Never dispose of the flow sensor in domestic waste.
ª Return the flow sensor to the manufacturer for correct disposal.
9 Technical data
The technical data of customized versions may differ from the data in these instructions. Please observe the
information specified on the product label.
Type MFS-1X MFS-2X MFS-3X
Characteristics measurement device
Measurement range 0.25 to 5.3 GPM (1 to 20 l/min) 0.5 to 10.5 GPM (2 to 40 l/min) 2.5 to 52.8 GPM (10 to 200 l/min)
Accuracy ±2% of reading
Repeatability 1%
Start of output signal
~ 0.13 GPM (~ 0.5 l/min) ~ 0.25 GPM (~ 1 l/min) ~ 1.3 GPM (~ 5 l/min)
Response time < 500 ms
Flow indication LED green, flow proportional flashing
Characteristics output signal
Frequency output:
- Pulse rate / K-factor 3,237 pulses/gal (855 pulses/l)
factory-set
3,237 pulses/gal (855 pulses/l)
factory-set
757 pulses/gal (200 pulses/l)
factory-set
- Resolution 0.0003 gal/pulse (1.2 ml/pulse)
factory-set
0.0003 gal/pulse (1.2 ml/pulse)
factory-set
0.0013 gal/pulse (1.2 ml/pulse)
factory-set
- Signal shape Square-wave signal y duty cycle 50:50 y NPN, 2 kΩ pull-up resistor (built-in)
- Signal current max. 20 mA, current limited
Analog output (optional):
- Signal current 4 to 20 mA
corresp. 0 to 5 GPM* (0 to 20 l/min*)
4 to 20 mA
corresp. 0 to 10 GPM* (0 to 40 l/min*)
4 to 20 mA
corresp. 0 to 52 GPM* (0 to 200 l/min*)
- max signal current ~ 26 mA
- max working resistance 250 Ω to GND
Electrical characteristics
Supply voltage 24 VDC ±10%
Current consumption max 80 mA
Electrical connection 4(5)-pin-plug M12x1
Electrical protection measures short-circuit proof (up to 30 V) / polarity protection (up to -30 V)
Degree of protection NEMA 4 (IP 65)
Process variables
Medium to measure Water and other conductive liquids
Min conductivity of the medium 50 µS/cm (lower conductivity affects the accuracy)
Max medium temperature 194 °F (90 °C)
Min medium temperature 32 °F (0 °C) (not freezing)
Ambient temperature 41 to 158 °F (5 to 70 °C)
Nominal pipe size (NPS) ¼'' ⅜'' ¾''
Nominal pressure 232 psi (PN 16)
Process connection ½” NPT male thread 1” NPT male thread
* other range on request