3 Installation
3.6 Electrical Installation
90 DC1 Variable Frequency Drive 04/16 MN04020003Z-EN www.eaton.com
3.6.2.4 Digital Input Signals
Control terminals 2, 3, 4, and 6 all have the same function and mode of 
operation as digital inputs (DI1 to DI4).
A logic level of +24 V (positive logic) is used:
• 8 - 30 V = High (logic “1”)
• 0 - 4 V = Low (logic “0”)
The internal control voltage from control signal terminal 1 (+24 V, maximum 
100 mA) or an external voltage source (+24 V) can be used for this. 
The permissible residual ripple must be less than ±5 % U
a
 
/
 
U
a
.
Optional modules DXC-EXT-IO110 and DXC-EXT-IO230 can be used to 
optically isolate the digital inputs (DI1 to DI4) and integrate them directly into 
control circuits with 110 V / 230 V. Values of 80 to 110/230 V AC will be 
recognized as a high signal,  Section 7.1.1, “DXC-EXT-IO… coupling 
module“, page 164.
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If you use an external voltage source, make sure to connect the 
0-V potentials of the externalvoltage source to the 0-V potentials 
of the variable frequency drive.
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Control terminals 7 and 9 are the common 0 V reference 
potential for all analog and digital input signals.