Commissioning
CP39xx-14xx-0010
37
Version: 1.1
4.3.3
Connecting cables and power supply
NOTE
Incorrect connection procedure
Incorrect procedure when connecting the cables and the power supply can cause hardware damage.
• Follow the documented procedure for connecting the cables and the power supply.
• Always connect all cables first and only then switch on the power supply.
• Please read the documentation for the external devices prior to connecting them.
The connections are located at the back of the Control Panel in the connection compartment. The interface
cables in the connection compartment are routed through the mounting arm tube. To gain access to the
connection compartment, first remove the side covers of the mounting arm adapter C9900-M759 (see
chapter 4.2.1
Installing the mounting arm adapter [
).
Before you can connect the cables and the power supply, you have to guide the cables into the connection
compartment.
Connecting cables
Make sure that you first ground the Control Panel (see chapter 4.3.2
then plug in all data transmission cables.
When connecting the Control Panel to an Industrial PC with UPS output, we recommend using this for the
connection. For CP-Link 4, we recommend connecting the CU880x transmitter boxes to the UPS output of
the PC.
Connecting the power supply
Cables with a maximum cable cross-section of 4 x 0.75 mm
2
can be used for connecting the power supply.
For long supply lines, use 4 x 0.75 mm
2
cables to achieve a low voltage drop on the supply line. There
should be at least 22 V at the voltage connector of the Control Panel, so that the Panel remains switched on
during voltage fluctuations.
Proceed as follows to connect the 24 V
DC
power supply unit:
1. Check the correct voltage of your external power supply.
2. Plug the voltage connector into the voltage socket on the Panel.
3. Screw the voltage connector to the voltage socket. Then check the screw connection.
4. Connect the Panel to your external 24 V power supply.
5. Switch on the 24 V power supply.
6. Calculate the voltage at the power supply plug.
In order to check the voltage at the power supply plug, you must first calculate the voltage drop on the supply
cable. You can orient yourself to the following calculation example:
• CP3918-14xx-0010 with CU8802 transmitter box or PCIe module
• Power consumption: 31 W
• Current consumption: 31 W / 22 V = 1.41 A
• Connection with 10 m two-core 0.75 mm
2
cable, although the supply cable length then corresponds to
20 m
• Constant of the specific resistance of pure copper: 0.0178 Ohm * mm
2
/ m
• Resistance of the supply line: 0.0178 Ohm*mm
2
/m * 20 m / 0.75 mm
2
= 0.0178 * 20 / 0.75 = 0.475 Ohm
With the listed data, you can now calculate the voltage drop on the supply line:
• 1.41 A * 0.475 Ohm = 0.7 V
With a CP39xx-14xx-0010 with CP-Link 4 and CU8803 transmitter box, you only have to pay attention to the
voltage on the supply line to the transmitter box. More detailed information can be found in the manual for
the
