7.3. Pressure transducer
The pressure transducer is an analogical
instrument with an output signal of 4-20 mA that
continuously reads the pressure in a system.
Features:
Standards: EN 50081-1, EN 50082-2.
Voltage: 8-28 V
Pressure range: 0-6; 0-10; 0-16 bar
Output: 4-20 mA
Working temperature: da 0 a +50 °C
Protection: IP 65
Hydraulic connection : G 1/4 male
Weigth: ~ 60 g
Electrical connection
Pressure
transducer
terminal box
supplied by us
7.4. Cascade mode
The EASYMAT frequency converters are
prearranged for use in pressure boosting sets with
up to 3 pumps in the following versions:
- Pressure boosting sets with 2 variable speed
pumps
- Pressure boosting sets with 3 variable speed
pumps
- Pressure boosting sets with 1 variable speed
pump and 1 fixed speed pump (single-phase)
7.4.1. Cascade mode installation
Connect the frequency converters on the delivery
pipes of the pumps, the installation must comply
with the provisions under paragraph 6.
Connect the pressure transducer to the delivery
manifold of the pressure boosting sets.
It is advised to install the pressure
transducers on the same point of the
delivery manifold and complete the
installation with a pressure gauge.
7.4.2. Cascade mode electrical
connection
Connect the supply cables to the motors and to the
power supply following the instructions under
paragraph 7. The power supply must comply the
provisions of the paragraph 4-5.
The connection with the power supply
must be made with interpositions of
magnetothermal bipolar switches (one for
each frequency converter).
For these frequency converters an earth leakage
circuit breaker or ground fault circuit interrupter,
type B.
This circuit breaker or interrupter must be marked
with the following symbols:
7.4.3. Cascade connection with
variable speed pumps
Electrical connection with 2 pumps
By means a proper cable make the connection of the
clamps number 4-5-6 of both frequency converters.
Electrical connection with 3 pumps
By means a proper cable make the connection of the
clamps number 4-5-6 of each frequency converters.
User must provide a jumper connection
into 1 frequency converter as shown in the
picture.
Check the correct connection sequence and
check that terminals of each cable are
connected on the clamp with same number.
To comply with the standards of
electromagnetic compatibility, for cable
length greater than 1 meter, it is
recommend the use of a shielded cable
with protection sheath connected on the
ground of both frequency converters.
7.4.4. Cascade connection with
1 variable speed pump
and 1 fixed speed pump
Connect the clamps 10-11 with a contactor with
max.250 Vac and 450 mA maximum resistive
current, connect to the contactor the power supply
-
+
4.93.413.1
2
2
1
1
3
3
1
3
2
4
+
RS 485
0
-
4.93.413.2
+
RS 485
0
-
+
RS 485
0
-
+
RS 485
0
-
21
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