Tecfluid CP420P - Manual (Page 3)

3
1 INTRODUCTION
The electronic transmitters CP420P … CH420P are panel mounting modules designed to
work with Tecfluid’s volumetric counters (series COVOL) and turbines (series TM). The
instruments are supplied already configured for the type of input.
The circuit is based on a microprocessor that, in function of the programmed pulses per
litre, calculates the flow rate and totalizes the volume that flows through the meter and
shows these values on a local indicator. The measuring units can be programmed.
The CH420P differs from CP420P in that it is also HART
TM protocol compatible.
2 INSTALLATION
2.1 Electrical connection
For the electrical connection, the CP420P has two screw terminals. In order to make
easier the connection, the description of the terminals is marked on the back cover of the
equipment.
For the electrical installation it is recommended to use multiple conductor cables with
individual cable sections in the order of 0.25 to 0.5 mm
2 in order to make it easier to
connect.
Peel the outside insulation to free the inner cables.
IMPORTANT NOTE: To ensure successful operation, it is recommended to do the
connection according the following points:
For output signals, use shielded cable when possible.
Move away the cables from strong sources of noise.
2.2.1 Power supply and current loop
Before connecting the power supply, you must be sure that the supply voltage is the
correct for the installation. The power supply voltage is indicated on the label of the
transmitter.
The connection is made in the terminal block marked as mA. The positive terminal of the
power supply is connected to the position + and the positive terminal of the load in the
position -. The negative terminals of the power supply and the load are connected
together. The instrument works in a 2-wire system, that is, the supply and signal line is the
same.