HBM PW15iA, Mounting Instructions, Page: 27 / 104

Structure and mode of operation
PW15iA
A4359-1.0 HBM: public
25
3 W
Voltage in V
Power demand in A
=
S
When switched on, the electronics briefly consume a
current of approx. 0.15 A. To ensure a safe start-up,
the power supply must be able to provide this current
without a limit being triggered. This is particularly
important when supplying several PADs from one
power supply. In contrast, the sustained loading is
calculated from the formula shown above.
S
Connection to a wide-ranging supply network is not
permitted as this often causes interfering voltage
peaks to be induced. Instead, a local supply must be
provided for the electronics (even when grouped).
S
The supply voltage must be insulated from the shield
potential. A connection from GND to the housing is
not required, but the max. potential difference must be
no more than 7 V.
S
The supply voltage ground wire (GND) is also used as
the reference potential for the interface signals and
the digital inputs/outputs.
S
In layouts with several digital load cells, the supply
can run together with the RS-485 bus lines in a 6-pin
cable (with HBM junction boxes, for example). Ensure
that there is sufficient wire cross-section provided, as
some cable sections will conduct the supply current
for all the connected electronics.
6.4 Digital inputs
You can select the switching threshold for the digital
inputs with the
SPL command. Note the different levels
for High and Low, according to the setting.