Tecfluid TH7 - Manual (Page 4)

4
1 INTRODUCTION
TH7 transmitters are microprocessed electronic position transducers. The instrument uses
the Hall effect to capture the field of a magnet. The resulting signal, after the micro-
controller processing, is converted into a current signal of 4-20 mA in a 2-wire loop. This
signal is proportional to the flow rate or the level height inside a tank.
2 MODELS
2.1 TH7
It is a 4 to 20 mA transmitter proportional to flow rate that incorporates a synchronized
pulse output. 4 mA corresponds to beginning of the scale. 20 mA corresponds to full
scale. If the transmitter is installed in a flow meter (series SC250 / DP), the cut off value
can be programmed (see section 9.3 in page 16). By default, the cut off corresponds to
the first point on the scale after the zero point.
In the case of level measurement (LP series), the current range corresponds to the scale
at all the points. There is no cut off.
2.2 TH7H
It is a TH7 transmitter that incorporates HART protocol compatibility. With this protocol the
user can change the measuring range of the 4-20 mA loop, and data like flow rate and
accumulated volume.
2.3 TH7T and TH7TH
They are the equivalent models to those of the sections 2.1 and 2.2, but in addition they
include a 8-digit totalizer (7 entire numbers and 1 decimal).
3 MOUNTING THE TRANSMITTER IN AN EXISTING EQUIPMENT
When the transmitter is to be fitted to an existing device, please follow these steps.
3.1 Kit contents
The kit contains the following elements:
Quantity Material Position
1 Transmitter 1
4 Screw DIN7985 M 3 x 4 A2 2
2 O-rings Ø 16 x 18,5 x 1,25 mm NBR-70 3
2 Cable gland IP68 4
2 Cable gland blanking plug 5
Kit TH7 or TH7H
Quantity Material Position
1 Totalizer 1
2 Screw DIN7982 B-2,2 x 9 Nº2 A2 2
Kit TH7T or TH7TH