ROTRONIC PF4 - Manual (Page 14)

E-M-PF4-V1_00
Rotronic AG
Bassersdorf, Switzerland
Document Code Unit
PF4 Differential Pressure Transmitter:
Instruction Manual
Instruction Manual
Document Type
Page 14 of 54
Document Title
© 2014; Rotronic AG E-M-PF4-V1_00
3.6 Relay
The PF4 provides a freely configurable internal isolated relay contact.
 Normally closed (NC)
 Common (COM)
 Normally open (NO)
The relay can be controlled by freely configurable alarms. The following can also be set:

Time delay
The relay is only switched on when an alarm endures for a certain minimum time.

Switch off when alarm finished
The relay automatically disengages when the alarm is no longer active; otherwise the relay remains
active until it is reset manually.

Maximum duty cycle
The relay stays on for at most the time set and is then switched off.
The relay can only be activated by a measured value. Assignment of more than one measured value is not
possible.
3.7 Service Interface
Using the HW4 software, the service interface (UART) allows device settings, loading of language data and
updating of the firmware. The service interface is located inside the housing. It is connected to the computer
with the HW4 software with an AC3006 or AC3009 connection cable.
Important:
The PF4 can be supplied with power through the service cable. The service cable provides insufficient power
for correct differential power measurement.
For sensor adjustment, the PF4 must be supplied with power from a suitable power source via the terminals
provided (K2-1: -/~, K2-2: +/~).