2 Installation
2.5 Connecting inputs
Operating instructions 05/10 MN05013003Z-EN www.eaton.com 37
Table 5: easy-DA input signals
2.5.3 Connecting analog inputs
The easy-AB, easy-DA and easy-DC basic units are provided with analog
inputs. Inputs I7 and I8, and if present I11 and I12, can be used to connect
analog voltages ranging from 0 V to 10 V. A simple additional circuit also
allows the analog evaluation of currents from 0 to 20 mA. The analog input
signals are converted to 10-bit digital signals.
The following applies:
• 0 V DC corresponds to a digital 0.
• 5 V DC corresponds to a digital value of 512.
• 10 V DC corresponds to a digital value of 1023.
2.5.3.1 Safety measures with analog signals
▶ Use screened, twisted pair conductors, to stop interference of the
analogue signals.
▶ For short cable lengths, ground the shield at both ends using a large
contact area. If the cable length is more than around 30 m, grounding at
both ends can result in equalization currents between the two grounding
points and thus in the interference of analog signals. In this case, only
ground the cable at one end.
▶ Do not lay signal cables parallel to power cables.
▶ Connect inductive loads to be switched via the easy outputs to a
separate supply voltage, or use a suppressor circuit for motors and
valves. Supplying loads such as motors, solenoid valves or contactors
and easy from the same supply voltage may cause interference of the
analog input signal when switching.
Voltage range of the input signals Input current
OFF signal ON signal
easy500/
easy700
I1 -I6 0-4 V DC 8 - 15.6 V DC 3.3 mA at 12 V
I7, I8 1.1 mA at 12 V
easy700 I9, I10 3.3 mA at 12 V
I11, I12 1.1 mA at 12 V
WARNING
Analog signals are more sensitive to interference than digital
signals. Consequently, greater care must be taken when laying
and connecting the signal lines.
Incorrect connection may lead to unwanted switching states.
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