Flowmetering

Local regulations may restrict the use of this product to below the conditions quoted.

Target flowmeters

In the interests of development and improvement of the product, we reserve the right to change the specification without notice. © Copyright 2016

TI-P193-01

MI Issue 4

TFA

Flowmeter for

Saturated Steam Service

Description

The Spirax Sarco TFA flowmeter is designed for use on saturated steam only and

operates on the target principle, by measuring the force produced on a target by

the fluid flow. This force is then converted into density compensated mass flowrate

or power and is transmitted via a single loop powered 4-20 mA and pulsed output.

TFA flowmeters also incorporate a totalised flow function and EIA 232C (RS232)

or EIA 485C (RS485) Modbus communications.

Sizes and pipe connections

The TFA flowmeter is of wafer design, available in the listed specified sizes suitable

for fitting between the following flanges:

DN25, DN32, DN40 and DN50

Flanged EN 1092-1 PN16, PN25 and PN40,

Japanese Industrial Standard JIS 20 and

Korean Standard KS 20

1", 11⁄4", 11⁄2" and 2"

Flanged ASME B 16.5 Class 150 and Class 300

Note:

The Spirax Sarco TFA flowmeter should be installed in pipework manufactured

to BS 1600, ASME B 36.10 Schedule 40 or EN 10216-2 / EN 10216-5 equivalent.

For systems with different standards / schedules, please contact Spirax Sarco.

TFA flowmeter

body

Direction of

flow within the

pipeline

Ensure that the direction

of flow in the pipeline

matches the directional

flow arrow on the body.

Flowmeter stem

Electronics

housing

Stainless steel 300 series

Where applicable the installation requires: 2 x Centralising bushes over

the lower two bolts of the flange connection -

See the selection table for 'Centralising bush kits' on page 4).

Note: The centralising bush kit must be ordered for the installation flange type

used on your application - See 'How to order' on page 4 for a typical example.

Technical data

IP rating

Power supply

Outputs -

proportional to mass

flow or power

Communication port

Performance

IP65 with correct cable glands

Loop powered

with optional RS485: 24VDC

4-20mA (not available with RS485 option)

Pulsed output:

V

max

28 Vdc R

min

10 kW

Modbus EIA 232C (RS 232C)

with optional RS485: EIA 485 (RS 485C)

Materials

Flowmeter body

Internals

Stainless steel 431 S29 / 300 series

Flowmeter stem

Stainless steel 300 series

Electronicshousing

Aluminium LM25

The TFA flowmeter has inbuilt electronics which give a density compensated output. The LCD display is incorporated within the electronics

head and can show totaliser, flowrate, power, pressure and temperature. An M750 display unit can be used to provide a remote display

function if required, utilising the 4 - 20 mA output.

System uncertainty, to 95% confidence (2 STD): (in accordance with ISO 17025)

± 2% of measured value from ≥ 20% and ≤ 100% of maximum rated flow

± 2% of full-scale value from ≥ 10% and < 20% of maximum rated flow

Turndown : up to 10:1

As the TFA flowmeter is a self contained unit, the uncertainty quoted is for the complete system. Many flowmeters claim a pipeline unit

uncertainty but for a true system uncertainty, the individual uncertainty values of any associated equipment, such as DP cells, need to

be added to the pipeline value.

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