Dwyer VFCII - Manual

The Series VFC Visi-Float ® flowmeters are available in
two basic styles, either back or end connected with direct
reading scales for air or water. Installation, operation, and
maintenance are simple and require only a few common
sense precautions to assure long, accurate, trouble-free
service.
CALIBRATION
All flowmeters are calibrated at the factory and normally will
remain within their accuracy tolerance for the life of the
device. If at any time you wish to re-check its calibration, do
so only with instruments or equipment of certified accuracy.
Do not attempt to check the Visi-Float
® flowmeter with a
similar flowmeter as even minor variations in piping and
back pressure can cause significant differences between
the indicated and actual readings. If in doubt, your flowme-
ter may be returned to the factory and checked for confor-
mance at no charge.
LOCATION
Select a location where the flowmeter can be easily read
and where the temperature will not exceed 120°F (49°C).
The mounting surface and piping to the flowmeter should be
free from vibration which could cause fatigue of fittings or
mounting inserts. Piping must be carefully arranged and
installed to avoid placing stress on fittings and/or flowmeter
body. Avoid locations or applications with strong chlorine
atmospheres or solvents such as benzene, acetone, carbon
tetrachloride,etc. Damage due to contact with incompatible
gases or liquids is not covered by warranty. Compatibility
should be carefully determined before placing in service.
PIPING
Inlet Piping:
It is good practice to approach the flowmeter inlet with as few
elbows, restrictions and size changes as possible. Inlet piping
should be as close to the flowmeter connection size as practical
to avoid turbulence which can occur with drastic size changes.
The length of inlet piping has little effect on normal pressure fed
flowmeters.
For vacuum service, the inlet piping should be as short and open
as possible to allow operation at or near atmospheric pressure and
maintain the accuracy of the device. Note that for vacuum service,
any flow control valve used must be installed on the discharge side
of the flowmeter.
VFC Series Visi-Float ® Flowmeter
Specifications - Installation and Operating Instructions
Bulletin F-48
SPECIFICATIONS
Service: Compatible gases & liquids.
Wetted Materials:
Body: Acrylic plastic.
O-Ring: Buna-N (Flouroelastomer available).
Metal Parts: Stainless steel.
Float: Stainless steel.
Temperature & Pressure Limits: 100 psig (6.9 bar) @
120°F (48°C).
Accuracy: 2% of full scale.
Process Connection: VFC: 1˝ female NPT back connec-
tions. End connections optional. VFCII: 1˝ male NPT back
connections. End Connections optional.
Scale Length: 5˝ typical length.
Mounting Orientation: Mount in vertical position.
Weight: 24-25 oz (.68-.71 kg).
Back Connections
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, IN 46361 U.S.A.
Phone: 219/879-8000 www.dwyer-inst.com
Fax: 219/872-9057 e-mail: [email protected]
1-1/2
[38.10]
3
[76.20]
4-1/2
[114.30]
10-1/2
[266.70]
1-1/2
[38.10]
8-1/2
[215.90]
2 NOM
[50.80] 1-1/32
[26.19]
1-1/8
[28.58]
1-1/8
[28.58]
1-1/2 HEX
[38.10]
1-3/4
[44.45]
1-1/2
[38.10]
11
[279.40]
WITH
BACK
CONNECTIONS
F-48 1002:F-48 1002 7/24/09 9:19 AM Page 1