Single-Phase Energy Measurement Box – Operating Instructions
© Festo Didactic
8130877
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6
Safety sockets
Unless otherwise indicated in the technical data, the following color coding applies for supply and signal
connections on components of the Festo Didactic Automation and Technology Learning System.
Colour
Meaning
Colour
Meaning
Voltage greater than safety extra-low voltage
E.g. mains voltage of 90 to 400 V AC per conductor
Mains conductor L1
(gray-brown)
24 V DC
(red)
Voltage greater than safety extra-low voltage
E.g. mains voltage of 90 to 400 V AC per conductor
Mains conductor L2
(gray-black)
0 V DC
(blue)
Voltage greater than safety extra-low voltage
E.g. mains voltage of 90 to 400 V AC per conductor
Mains conductor L3
(gray-dark gray)
Safety extra-low voltage
Signal input/output
Functional earth
(black)
Voltage greater than safety extra-low voltage
E.g. mains voltage of 90 to 400 V AC per conductor
Mains conductor
(gray)
Neutral conductor
(gray-blue)
Grounding conductor, configuration as 4 mm safety
socket
(green-yellow)
Protective grounding terminal as PE+ contact, delivery
status
(green-yellow)
