References

High-efficiency
Heat Exchanger Systems
Sample Application:
Residential District in Nottingham, UK

District Energy

SMART IN FLOW CONTROL.

Applications
Automation

ControlCPU module
Scalable automation system

Pressure-independentcontrol valve (PICV)Integrated web visualization

Electric control valveE-mail, text message

Adjustable flow rate

Modbus/BACnet

Independent of networkpressure conditions

Web terminal

Safety temperature monitor

Multi-touch panel

Protects domestic systems
against excessive temperatures

7" color TFT display
Power over Ethernet (PoE)USB port for historical data

Alerts CPU of excesstemperatures
Automatic reset

Modbus-GPRS gateway
Access using Internet/GPRS

Safety temperature limiterwith pressure element

Remote maintenanceShuts off heat sourceConnection of heat meters

Protects domestic systems
against excessive pressure

Alarm management

Alerts CPU of triggered
fail-safe action

Heat exchangers

Smart Automation

Heat exchangers
Sequence switched basedon operating hours
Error detection
Return flow temperature
limitation

Double pumpsDifferential pressure control
Pump bypass
Manual modeMeteringConnection using M-bus
Automatic logging
Data export for billing

Pump protection
Minimal flow rate for pumps
Defined pressure drop at
minimal flow rate

SMART IN FLOW CONTROL.

References: District Energy
Heat Supply in Residential Areas

Flow Under Control

Heat Exchanger Sequence

An example of smart automationis the residential area scheme
implemented in the English city ofNottingham. Vital Energi, Enviro
Energy, and SAMSON Controls
joined forces to create one plant
for two residential areas. They
are connected to the existing district heating network using a heattransfer station.

The electric control valves in heattransfer stations take over variouscontrol tasks and, as a result, theymust meet a whole range of requirements.

Each heat exchanger is fitted with
an electric control valve in the primary circuit and a shut-off butterfly valve in the secondary circuit.
The flow and return flow temperatures are measured in the supply
line and in the customer circuit,and binary operating and fault
messages are recorded. Thesemessages are transmitted to theTROVIS 6600 Automation System.

At each station, heat exchanger
sequence control is implemented
but sized and configured differently to cater for the different capacities consumed in the secondary circuit. The first station comeswith two heat exchangers, eachdelivering 600 kW at a connection size of DN 65. In the primarycircuit, the temperature ratio is110 °C to 70 °C, in the secondary circuit 85 °C to 65 °C. In thesecond station, delivery of eachheat exchanger is 1 MW with aconnection size of DN 80 installedin the primary circuit and DN 125
in the secondary circuit.

The control valves are designed toensure stable operation and accurate control regardless of thedifferential pressure in the district heating network. The plantcomponents must be operated
at a certain flow rate to distribute the heat capacity to the heatexchangers, protect the pumps,
and keep the supply pipes at acertain temperature. Additionally, the valves ensure that certain operating temperatures andpressures are maintained. For
this purpose, Type 42-36 E andType 2488 Pressure-independent
Control Valves are used in combination with Type 3374-21 andType 5825 Actuators with fail-safe
action.

The system is scalable with thecentral TROVIS 6610 CPU Module performing the smart plantmanagement. The CPU module
is a freely programmable controlunit with 20 universal inputs tooptionally record binary or analog signals. In addition, twelve
binary outputs and eight continuous voltage outputs are available.
The system can be extended using
different I/O modules, i.e. it canbe adapted individually to matchcustomer requirements.

SAMSON AG · AKTIENGESELLSCHAFT
Weismüllerstraße 3 · 60314 Frankfurt am Main
Germany
Phone: +49 69 4009-0 · Fax: +49 69 4009-1507
E-mail: samson@samson.de
Internet: www.samson.de

SMART IN FLOW CONTROL.

SAMSON CONTROLS LTD
Perrywood Business Park, Honeycrock LaneRedhill, Surrey RH1 5JQ
Phone: +44 1737 766391 · Fax: +44 1737 765472
E-mail: sales@samsoncontrols.co.uk
Internet: www.samsoncontrols.co.uk

2015-11 HD · WA 346 EN

ReferenCES