Tecomat Foxtrot – system design
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1.1.1.
Power supply of basic module CP-1004
For proper functioning, the module requires smoothed direct current supply voltage 24 VDC (in case of
power supply backup by batteries, the system can be supplied by a 27.2 VDC source - we recommend to
use the PS-50/27 power supply source). The maximum power consumption of the system (under full load
- closing of relay inputs, with an additional submodule fitted and with active communication) is 8 W.
The module power supply is galvanically connected with the inputs DI0 ÷ DI7, the CH1 communication
interface, the CIB1 interface and the TCL2 system channel. Also in case the CH2 channel is fitted with a
submodule with galvanically non-isolated I/O circuits, these circuits are galvanically connected with the
power supply of the system. The common pole is the GND terminal (terminals A3, terminals B1).
NOTE
When applying the system, the common pole (galvanic connection) of the above-mentioned I/O parts of
the module should be taken in account – especially in case of supplying from more positions, more power
supply sources or risk of occurrence of ground loops.
SELV:
If the power supply source fulfils the
parameters
of SELV sources according to ČSN 33 2000-4-41, than all
I/O circuits of the system fulfil the SELV requirements. Also in cases when the relay outputs switch the
low voltage circuits (isolation of relay outputs from the internal circuits of the system is 4 kV AC).
Source parameters:
Usually, most of power supply sources with 24V= output stabilised voltage comply for suit. An non-
stabilised power supply source can also be used, but attention should be paid to the output voltage (for a
power supply source with a high output, the output voltage might exceed the permissible value.
Source output determination:
A source with an output of min. 15W is optimal to supply an individual control system. If further circuits
are supplied from this source, its output has to be increased proportionally. In case a source with non-
stabilised output is used, the permissible range of the supply voltage should be followed, especially in
cases when power supply sources with a high excess output are used.
Power supply protection:
The power supply input (terminal A4) is not protected by an internal fuse. We recommend using a front-
end external fuse before the modules power supply with a recommended nominal value of
T500L250V
.
Increasing resistance
of module power supply sources:
To ensure a trouble-free operation also in exceptional situations (thunder strokes, generally bad condition
of the distribution network or effects of close of power devices having negative effects to the distribution
network), we recommend using elements ensuring the resistance of the sources against unfavourable
effects of the environment. Detailed information on methods how to increase the reliability can be found
in the documentation TXV 001 08, chapter 2.
