RHEONIK RHE26, Инструкция по установке и запуску

Страница: 12 / 44

RHE26/27 Installation & Startup Guide – Doc. No. 8.2.1.06 – Ver. 1.40 12
3.2.2.4 AC and DC Supply
Units with power supply option U1 can be operated from both DC and AC power supplies. Both
can be connected simultaneously and the RHE will be powered up as long as one of the supplies
is present and within operating tolerance.
The U1 power supply option is designed
to be used where, for instance, battery
backup of the flow meter is required.
Connect an AC supply to terminal 23 and
24 (see section 3.2.2.3) and a DC supply
to terminals 20 and 21 (see section
3.2.2.2).
If both power supply options are
connected, avoid a DC supply voltage
higher than 23V to ensure that the AC
power supply is used. If the AC supply is
disconnected, the DC supply will be used
to power the RHE until the Voltage
present drops below 10V.
An RHE/RHM flow meter has a typical
power consumption of around 3W. If a
12V / 100Ahr battery is used as the DC
input to the RHE, the unit would operate for more than 10 days after the AC supply had been
disconnected.
Control Inputs and Outputs
In general, shielded cables should be used for cable connections longer than 0.5m. For cable
connections longer than 3m, it is recommended that ferrite filter beads are installed close to the
RHE terminations to help avoid RF EMI.
3.2.3.1 Digital Outputs
The RHE26 has two digital outputs. The RHE27 can be supplied with up to four digital outputs.
Outputs DO1 and DO2 are universal outputs and can be used as frequency, pulse or
control/status outputs.
Outputs DO3 and DO4 are control/status outputs only.
Digital outputs are push-pull outputs compliant to IEC 60946. They can drive loads connected to
ground and loads connected to +24V.
Figure 7: Universal Power Supply