Combination Leakage Protection

System LMI-C

system LMI-C Ill.: system LMI-CB/X OptiTight®; Application:
  Small institutions

  • Water, Forward and Return flow meters
  • Cutoff and non-return valves
  • Control Unit

Monitoring Functions

Leakage District Heating:
Forward and Return flows are monitored continuously. compensating for volume and meter differences. If a preset flow difference limit is exceeded, leakage alarm is issued and the installation is cut off.

Seepage District Heating: OptiTight®
The patented OptiTight® mechanism employs individual control of the cut-off valves to test the installation tightness one or more times daily, whereby even minute seepage may be detected.

Leakage Supply Water:
The system permits the continuous discharge of a preset amount of water. If this amount is surpassed in a single discharge, a Max Alarm is issued, and the water supply is cut off. ¹

Seepage Supply Water:
The system checks that water flow in the installation can drop and remain below a preset level for a preset time duration, and will issue a Seepage Alarm and cut off the water supply ¹ if this fails to occur daily.

System Error:
The system checks that the flow meter in the water supply issues impulses regularly, unless the Holiday function is active.
The system checks the Forward/Return flow meters against each other, whereby meter blocks and occurring defects are immediately discovered.
Whenever a valve is closed - manually or by alarm -  the system checks its tightness.
In case of component failure, a System Alarm is issued. The installation is cut off on meter errors.

Supply Error:
The system monitors the mains supply and all internal supplies. If either of these fail, a Supply Alarm is issued. This may not cause cutoff of the installations.

Alarm Functions

On leakage and meter errors, system LMI-C will cut off the affected installation, issue visible and audible alarms, and activate the relevant alarm relay.
Supply errors are reported via the alarm relay, and possibly also visibly and audibly.
Valve errors are reported visibly.

Types LMI-CB-V0/B and LMI-CB-V0/X are used where firefighting hoses or sprinklers are part of the monitored supply water installation. These types must always be connected to an alarm- or dialout system.


Controls and Indicators:
Operation, alarm and status indicators, buzzer.
Buttons for temporary free discharge selector, holiday function (Supply water) and alarm acknowledge Supply Water/District Heating.

Leakage Monitor District Heating:
Base measuring period 210 sec.
Truncation at high flow rates.

Seepage Monitor District Heating (OptiTight®):
Activation: 1, 2, 3, or 4 times daily.
Base time 02:00 + 24 / 2*12 / 3*8 / 4*6 hours. Delay up to 1 hour if consumption is high.
Sensitivity up to 1 litre/hour.

Leakage Monitor Supply Water:
Permissible single discharge selectable 125, 250, 500, or 1000 litres.
Flow minimum to terminated discharge 15 l/h.
In holiday mode, permissible single discharge is 20 litres regardless of setting.
Free discharge of preset duration 1-8 hours.

Seepage Monitor Supply Water:
Seepage tolerance 2, 4, or 8 litres in 30, 60, or 120 minutes. Observation interval 24 hours.

Mains Connection
230V 50Hz L/N/PE via external key switch. Power Consumption max 20VA.


Liquid Sensor Attachment:
System LMI-C accomodates via interface ILS-C up to two liquid sensors type LS-X, whereby the system offers point protection of particularly sensitive areas so that either installation may be cut off on Liquid Sensor alarm if desired.

By attachment of an external SMS-alarm to the alarm relay output, system LMI-C can ship a text message to a selected mobile phone number.

system diagram LMI-C
1: Control Unit
3: Forward Flow Meter
5: Return Cutoff Valve
7: Water Flow Meter
2: Forward Cutoff Valve
4: Return Flow Meter
6: Non-return Valve
8: Water Cutoff Valve
System Supply Water Section District Heating Section
LMI-CB-V0/B Like system LMI-B1,5-V0 Like system LMI-F1,5
LMI-CB-V0/X Like system LMI-B1,5-V0 Like system LMI-F2,5
LMI-CB/B Like system LMI-B1,5 Like system LMI-F1,5
LMI-CB/X Like system LMI-B1,5 Like system LMI-F2,5

EAN/UPC ordering codes here

Download System LMI-C datasheet in pdf-format