NOVUS AUTOMATION 1/2
TxIsoLoop-1 / TxIsoLoop-2
LOOP-POWERED ISOLATORS – USER GUIDE V1.0x
1. INTRODUCTION
TxIsoLoop-1 and TxIsoLoop-2 galvanic isolators are devices used
for electrical isolation of 0(4)-20 mA current signals. Its purpose is to
avoid measurement errors typically found in installations that have
problems with electrical potential difference and ground loops.
These isolators do NOT require an electrical power supply. The
energy obtained by passing the electric current through the insulator
input actively generates the output current.
2. FEATURES
•Galvanic isolation between input and output.
•Models with one or two input/output channels.
•The device does not require a power supply.
•High accuracy.
3. SPECIFICATIONS
•Input signal: 0(4) to 20 mA (Check minimum current for proper
operation)
•Voltage drop − Input/output without protection (Vdrop): < 3 Vdc
•Voltage drop − Input/output with protection (Vdrop): < 5 Vdc
•Output signal: 0(4) to 20 mA
•Max. load (RL): 1450 R
•Total accuracy: 0.2 % @ 0 to 60 °C / RL = 250 R
0,3 % @ -20 to 75 °C / RL = 250 R
•Minimum operating current: > 0.1 mA
•Maximum input current: < 40 mA
•Response time: 2 ms @ RL= 250 R
•Current limit: 31 mA
•Electrical isolation: 3000 Vac / 10 seconds
240 Vac continuous
•EMC: EN 61326-1 (without performance degradation)
•Work environment: Temperature: -20 to 75 °C
Relative humidity: 20 to 90 %
•Housing: ABS (60 %) + PC (40 %)
•Protection index: IP40
•Wire gauge for connections: 0.14 to 1.5 mm²
•Recommended torque: 0.8 Nm
•Polyamide terminal enclosure.
4. ELECTRICAL INSTALLATION
To ensure perfect operation of the TxIsoLoop isolator, the circuit
where the isolator input is connected must provide a minimum
electrical voltage (V1).
You can supply the electrical voltage in two ways:
1. The device that generates the current signal is of the active type
(source), where it provides the necessary electrical voltage
itself.
Figure 1 –TxIsoLoop connections with source type device
With type source devices (transmitters, controllers, etc.), this voltage
is provided by the device itself).
The minimum voltage value to be supplied by the generator can be
calculated using the formula below:
V1= Vin Where: Vin = Vdrop + ( Iout(max) x RL)
in
out
2. With sink type devices (2-wire transmitters), the energy is
provided by an external power supply in series in the loop, as
shown in Figure 2.
Figure 2 –Connections on the TxIsoLoop with sink type devices
In this option, the inserted source must provide enough voltage to
meet the needs of the current generating device (generator,
transmitter, controller, etc.) and the isolator.
The minimum voltage value to be supplied by the power supply can
be calculated using the formula below:
V1= Vb+
Vin
Where: V1= Voltage from the source inserted
into the circuit
Vb= Minimum voltage of the generator
Vin = Vdrop + ( Iout(max) x RL)
in
out
