District Heating Leakage Protection System FBU/FXU


District Heating Leakage Protection System FBU/FXU employs measurements of volume flow from two ultrasonic meters, which are fetched regularly from a Kamstrup MULTICAL®601 or 602 heat meter to which the flow meters are attached.

Two monitoring functions are employed with the fetched flow volumne data for protecting the installation from leakage, as the KMP-F closes the cut-off valves when a leak is detected by any monitor.

Component errors reported in the heat meter's INFO code are propagated by the KMP-F as System Fault alarms.


System Diagram FBU/FXU


Alarm and Event Log
FBU/FXU maintains a log of the most recent 250 events, such as Power Down, Power Up, Alarm and Error messages, Alarm Acknowledge and Autoreset, External Control Input change, State change and Sequence execution.


Jumper Log
FBU/FXU maintains a log of the 15 most recent changes to the jumper settings.

These logs serve to document events surrounding actual incidents in the installation.

System Capacity and head loss Dimensions
Nom. Cap.
Qn (m³/h)
 ΣΔp@Qn Equivalent
Kwc (m³/h)
(mWc) (kPa) Flow Meter Valves Check Valve
FBU 1,5 3,5 35 2,6 ½" x 110 mm ½" x 77 mm ½" x 48 mm
FXU 2,5 3,1 31 4,5 ¾" x 190 mm ¾" x 77 mm ¾" x 53 mm


Variant -M2 is a complete new delivery.
Variants -M1 and -M0 are used with a suitable existing Kamstrup heat meter.
Note that the heat meter must be grid powered for use with FBU/FXU.

Delivery FBU/FXU

Variant (suffix) -M2 -M1 -M0
FBU/FXU Controller 1 1 1
Cut-Off Valves 2 2 2
MULTICAL®602 1 0 0
Flow meters 2 1 0
KMP Data Module 1 1 1

side 1

EAN/UPC ordering codes here

Download System FBU/FXU data sheet in pdf format