Specifications; Optional 4-20 Ma Current Output - Teledyne HASTINGS HFM-300 Instruction Manual

1.2. Specifications

Accuracy...................................................................................... < ±0.75% full scale (F.S.) at 3
Repeatability (includes noise) ................................................................................ ±0.2% F.S.
Maximum Pressure ....................................................................................... 500 psi [3.45 MPa]
Pressure Coefficient ................................................ <0.016% of reading/psi [0.0015%/kPa] (N2)
Operating Temperature ................................................. -20-70°C in non-condensing environment
Temperature Coefficient (zero) .......................................... Maximum ±0.12% F.S./°C (-20-70°C)
Temperature Coefficient (span) ................................... Maximum ±0.08% Reading/°C (-20-70°C)
Leak Integrity ................................................................................................ <1x10
Flow Ranges ...................................................................... 0-5 sccm to 0-25 slm. (N2 Equivalent)
Standard Output ........................................................................... 0-5 VDC. (load min 2k Ohms)
Optional Output ............................................................................ 4 -20 mA. (load < 600 Ohms)
Power Requirements .............................................................. ±(14 - 16) VDC @ 70 mA (meters)
Wetted Materials ................................................................................ stainless steel, nickel 200
Attitude Sensitivity of zero ............................................... < ±1.4% F.S. for 90° without re-zeroing
Weight ........................................................................................... HFM-300 = 1.95 lb. [0.88 kg]
Electrical Connector ............................................................................... 15 pin subminiature "D"
Available fitting options (all tube fittings are 2 piece compression fittings)
Fitting Options ............................................... ¼" tube, 1/8" tube, 6 mm tube, ¼" VCR
Face Seal to Face Seal Length ................................................................ 1.88" (47.75 mm) VCR

1.3. Optional 4-20 mA Current Output

An option to the standard 0-5 VDC output is the 4-20 mA current output that is proportional to flow.
The 4 - 20 mA signal is produced from the 0 - 5 VDC output of the flow meter. The current loop output
is useful for remote applications where pickup noise could substantially affect the stability of the
voltage output.
The current loop signal replaces the voltage output on pin 6 of the "D" connector. The current loop
may be returned to either the signal common or the -15 VDC connection on the power supply. If the
current loop is returned to the signal common, the load must be between 0 and 600 ohm. If it is
returned to the -15VDC, the load must be between 600 and 1200 ohm. Failure to meet these
conditions will cause failure of the loop transmitter.
The 4-20 mA I/O option can accept a current input. The 0-5 VDC command signal on pin
replaced by a 4-20mA command signal. The loop presets an impedance of 75 ohms and is returned to
the power supply through the valve common.
Manual: 151-032015 300-302 Series
(±1.0% F.S. for >10 slm versions)
(With high pressure option) 1000 psi [6.9 MPa]
See pressure section for higher pressure errors
±(14 - 16) VDC @ 185 mA (controller)
Class 2 power 150VA max
Kalrez® (controller only)
(N2 at 50 psig [446 KPa])
HFC-302 = 2.45 lb. [1.12 kg]
9/16"-18 Female thread, Surface Mount
-9
std. cc/s.
® ®
, ¼" VCO ,
®
14 can be
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