FW_F126PELTP_v1702_02_EN
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Reed-switch:
The F126-P is suitable for use with flowmeters which have a reed-switch. To avoid pulse bounce
from the reed-switch, it is advised to select REED LP
– low-pass filter (read chapter 3).
Fig. 21: Terminal connections - Reed-switch signal input (typical)
NAMUR-signal:
The F126-P is suitable for flowmeters with an Namur signal. The standard F126-P is not able to
power the Namur sensor, as an external power supply for the sensor is required. However, a 8.2V
sensor supply voltage (terminal 11) can be provided with power supply type PD, PF, PM.
Fig. 22: Terminal connections - NAMUR signal input (typical)
Terminal 20-22; Temperature input TP - PT100:
The temperature of the inlet flow will be measured with sensor A. Two types of PT100 elements can
be connected: 2 or 3-wire. The temp coefficient for the RTD is 0.00385 ohms/ohms/°C. The Ro is
100 ohms at 0.0°C.
Terminal 26-31: type CB / CH / CI / CT - communication RS232 / RS485 / TTL (option)
For connections, refer to figure: Overview of terminal connectors - Standard configuration and options
Full serial communications and computer control in accordance with RS232 (length of cable max.
15 meters) or RS485 (length of cable max. 1200 meters) is possible.
When using the RS232 communication option, terminal 27 is used for supplying the interface.
Please connect the DTR (or the RTS) signal of the interface to this terminal and set it active (+12V).
If no active signal is available it is possible to connect a separate supply between terminals
26 and 27 with a voltage between 8V and 24V.
Terminal 00 - 01: type ZB backlight (option):
If the unit is supplied with a power supply:
type PD, PF or PM, the backlight supply is integrated.
type PX, use the terminals 00 and 01 to supply the backlight.
The backlight intensity is set in the setup menu: Display.
