wtw DIQ/S 282, Operating Manual, Page: 21 / 186

DIQ/S 28X Installation
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to provide general and consistent protection via gas overvoltage surge
arresters.
3.5 Drawing up the power rating
General
information
The IQ S
ENSOR
N
ET
supplies all components with low voltage as well as digital
communication via a shielded 2-wire line.
Because of this characteristic the energy consumption of all components must
be taken into account (power rating) when planning an IQ S
ENSOR
N
ET
system.
The energy consumption determines whether an additional power module is
necessary.
Power rating -
why?
All components in the system require a specific level of electrical power for oper-
ation. Thus, it is necessary to draw up a power rating after selecting the desired
components. At the same time, this can determine whether the entire power
requirement of all components (consumers) is covered by the internal power
supply module of the Universal Transmitter. If this is not the case, the power
available in the system must be increased by further MIQ power supply
modules.
To operate the DIQ/S 28X safely, the power rating must meet the following
condition for continuous operation and for power peaks:
Maximum allowed
power delivery of
IQ S
ENSOR
N
ET
components
The maximum allowed power delivery of the power supply components of the
IQ S
ENSOR
N
ET
is given in the following table:
Only IQ S
ENSOR
N
ET
products may be used in the IQ S
ENSOR
N
ET
.
Sum of the power requirement
(continuous) ≤ Sum of the power delivery
(continuous)
Sum of the power requirement
(peak) ≤ Sum of the power delivery
(peak)
The power rating provides an initial guide value. In specific limiting
cases, the power supply may be insufficient despite the positive
power rating.
Example: Temperatures above 47 °C (117 ° F) reduce the available
power output of the DIQ/S 28X (see T
EMPERATURE DEPENDENCY
(
DEGRADATION
)
OF THE MAXIMUM ALLOWED
P(
CONTINUOUS
), page 25).
The reduced power output may possibly have to be compensated
for with further MIQ power supply modules.