IOM REF Iss 5 August 3 fo 1 egaP 0401RCE 1002

The meter is mounted vertically. Care should be taken toavoid valves, sudden bends or other flow disturbancesimmediately upstream of the flowmeter. RH type units havebuilt in flow straighteners. Separate flow straighteners arerecommended for MH and LH type meters.

A GUIDE TO THE INSTALLATION, OPERATION AND MAINTENANCE OF

Reflux Series Flow Transmitters

mm

Model / Size (Note: BSPF threads)

A B C D E

RF 3/8"RH 175 80 56 16 210

RF 1/2"MH 220 125 80 20 240

RF 1”MH 220 125 80 20 250

RF 1”LH 355 125 80 20 385

Mechanical Installation.

Units are supplied fully assembled and suitable for

direct mounting into pipe work. Pipe work should be

aligned prior to connection in order to avoid excessive

side stress. Four holes at the rear of the frame allow

for fixing to a panel if required.

When screwing pipework or fittings to the meter, the

top and bottom hexagonal nuts should be supported by

spanner to avoid damage to internal seals.

Care should be taken to minimise the use of magnetic

materials in installation, as these can affect the

transmitter calibration. Reflux calibration software and

a PC interface unit can be used to carry out in-situ

calibration against the flow scale points.

Note: maximum operating pressure is 20 bar for glasstube ranges and 8 bar at 20°C, de-rated to 3 bar at60°C for plastic tube versions. C

D B

E

A

VAF Fluid-Technik GmbH, Gottfried-Schenker-Str. 12, 09244 Lichtenau +49 (0) 3720 8814 0 www.vaf-technik.de

IOM REF Iss 5 August 3 fo 2 egaP 0401RCE 1002

Electrical InstallationThe unit is powered by a 2-wire 4-20mA loop wire requiring the connections shown below: Red wire : positive power supply voltage Blue wire : negative power supply voltage Green wire : Used for communication, factory calibration and retro-fitting.

(Not used in normal operation) Supply voltage : 8V to 28VDC

The maximum allowable loop resistance is a function of the supply voltage. Use the equation below to determine the maximum resistance for your application: Rmax = Supply Voltage – 8V

0.02A

For units fitted with an integral terminal block housing, the wires above are connected as follows:

Terminal 1: Green wire Terminal 2: Red wire Terminal 3: Blue wire

Hazardous AreasFor intrinsically safe operation (Tia units only), barrier selection, cable parameters and power supply limits must be in accordance with the entity parameters shown on the label. If an intrinsically safe unit is used without a barrier, this apparatus may no longer be considered as intrinsically safe. It is the customer’s responsibility to clearly mark the apparatus when intrinsic safety is no longer valid.

Do not connect the green wire (keep it floating) when the transmitter is in normal operation. The green wire should not be extended.

For TnA type units, a barrier is not required, although installation is limited to zone 2 applications for gases and vapours, and non-hazardous areas.

Note: The power supply voltage determines the maximum allowable resistance of the loop. Always be sure that the voltage on the transmitter is within specifications.

AdjustmentThe Reflux transmitter can be adjusted / calibrated with the help of a PC-program and a small interface plugged in any RS232 serial PC-port. The calibration data is stored into non volatile memory in the transmitter. After calibration the unit is a standalone functioning device.

Ammeter

+

-8..28V

4..20mA Red

Blue

VAF Fluid-Technik GmbH, Gottfried-Schenker-Str. 12, 09244 Lichtenau +49 (0) 3720 8814 0 www.vaf-technik.de

IOM REF Iss 5 August 3 fo 3 egaP 0401RCE 1002

Operation.

Transmitter Retro-fittingIf a Reflux flowmeter housing has been installed without an integral 4 to 20mA transmitter unit, it is possible to retro-fit on site:

1. Firstly pass the cable through the rubber grommet in the flowmeter housing, from inside to out.

2. Mount the transmitter inside the housing using the screws and spacers provided.

3. If the Calibration PC software and interface are available, these can be used to calibrate the transmitter to the scale on the tube. See separate instructions.

4. If the calibration software is not available and the transmitter has been supplied calibrated for the range being used, power should be applied and the unit zeroed by connecting the green wire to the blue wire for at least 2 seconds, with the float at its rest position.

5. The transmitter is now ready for operation.

For best results the flowmeter should be checked to be vertical and anyconnections checked for leakage. The flowrate can be read by viewing the top float edge against the graduatedflowscale. The 4 to 20 mA output is calibrated against the flowscale with20mA representing the full scale value, e.g. 200L/min of air, for the scale onthe left. A low point cut-off is normally set at around 8 to 10% of full scale.Once the flow falls below this position, the current output will drop to 4mA(zero), indicating that the flow rate is below the range of the instrument. Providing the materials are compatible with the metered fluid and theoperating limits observed, there should be no requirement for maintenance.In the event of breakage, a change of duty, or the need to clean a tube thefollowing section may apply.

Flow tube replacement.After isolating and venting/draining the meter section remove the unit fromthe pipeline. For 3/8”RH type units remove the top and bottom plasticwedges and by sliding the o’ring adapters, remove the glass tube. For allother size units, disconnect the top and bottom connections by removing theblock retaining clips, allowing the tube to be removed, cleaned or replaced. Reassemble ensuring the top and bottom tube 'o'-rings are engaged in thetube bore.

VAF Fluid-Technik GmbH, Gottfried-Schenker-Str. 12, 09244 Lichtenau +49 (0) 3720 8814 0 www.vaf-technik.de