The line lengths and cross-sectional areas depend on the actuators power consumption and the permissible voltage drop of the connection lines to the actuators. Determine the necessary line length from the following diagram and the formulas.
Note
To determine the line length and cross section, adhere to the permissible operating voltage tolerance at the actuator (see chapter 8, "Technical data") in addition to the permissible voltage drop between the signal and supply lines (see table below).
Permissible voltage drop
The line sizing between the controller and the actuators depends on the actuator type used and is determined on the following basis.
| Type | Operating voltage | Line |
Max. permissible voltage drop |
GMA12..1 GMA13..1 |
AC/DC 24 V | G0, G Y1, Y2 |
4 % each (tot. 8 %) of AC/DC 24 V |
| GMA16..1.. | AC 24 V |
G0, G |
4 % each (tot. 8 %) of AC 24 V |
DC 24 V |
G0, G |
1 % of DC 10 V |
|
GMA32..1 |
AC 230 V | L, N |
2 % each (tot. 4 %) of AC 230 V |
Notes on the G0 line
(GMA16..1)
Consider the following criteria:
For modulating control and DC 24 V operating voltage:
The permissible positioning signal error caused by a voltage drop in the line current (direct voltage mean value) on the G0 line must not exceed 1%.The G0 line's voltage drop caused by surges in the DC circuit in the actuator may not exceed 2 Vpp.
In the case of improper sizing of the G0 line, actuator load changes may cause natural oscillation due to a change in the DC voltage drop.
The supply voltage loss at AC 24 V may not exceed 8% (4% over G0 line).
Line length/consumption AC/DC 24 V
The diagram applies to AC/DC 24 V and shows the permissible line length L as a function of consumption P and as a parameter of the line cross sections.
Notes on diagram
The values in [VA, W] on the P-axis are allocated to the permissible voltage drops (ΔU/2U = 4 %) on line L as per the above table and to the P&I diagram.
C is the primary power consumption for all actuators connected in parallel.
P&I diagram:
Voltage drop on the supply lines
Formula for line length
The maximum line length can be calculated using the following formula.
Operating voltage |
Perm. voltage drop / line |
Formula for line length |
AC/DC 24 V |
4 % of AC/DC 24 V |
L = |
1 % of DC 10 V |
L = |
|
AC 230 V |
2 % of AC 230 V |
L = 46 • |
[m]
[m]
[m]A Line cross section in [mm2]
L Permissible line length in [m]
P Power consumption in [VA] or [W];
The value is printed on the actuator's type plate.
I(DC) DC current portion in line G0 in [A]
Line length for actuators connected in parallel
The following sections show how to determine the permissible line length and cross sections for the various actuators based on examples.
The examples for actuators connected in parallel apply to the following arrangement:
Assumption
The line resistances of L2 are equal and can be ignored for L1. Separately calculate the permissible line lengths L2 for other connections (ring, star-like).