Trend Control Systems Ltd has launched the first two models in a new generation of building energy management system (BEMS) controllers. Though small in size, the Trend IQ411 and IQ412 both offer a combination of advanced capabilities not found on any other building services controller, even much larger ones. The versatile new units – which incorporate a range of features that simplify installation, engineering and commissioning – are ideal for energy efficient, highly distributed local control of services such as underfloor heating, natural ventilation, small air handlers and air conditioning terminal units.
Ethernet connectivity comes as standard on all variants of the IQ411 and 412, as does a web server. In addition, there are BACnet versions and versions of the controllers that can be connected to a Trend LAN. This allows for different customer preferences and requirements, even if they change in the future. The new controllers are fully compatible with earlier generations of Trend control and monitoring equipment and can be seamlessly integrated within existing Trend BEMS.
The IQ411 and 412 are both 11-point controllers. Each has 3 universal and 2 digital inputs; the IQ411 has 6 solid state digital outputs whereas on the IQ412 there are 4, plus 2 analogue outputs. The profile and dimensions of their DIN rail mounting casework allow them to be fitted in small, low cost electrical enclosures. Installation costs are further reduced as the controllers can be located close to the plant they are regulating, which minimises wiring requirements.
Other controller features have significantly cut the time needed for set up and commissioning. For instance, unlike competitors’ controllers the IQ411 and 412 do not incorporate DIP switches for setting their network addresses. Instead, this is done via the network using Trend’s standard engineering tool (SET), which is far less time consuming. This process of ‘soft’ addressing can be further simplified by combining it with barcode identification – eg, scanning an identifying label on the controller, which results in automatic assignment of the correct address.
The IQ411 and 412 share the same flexible firmware structure that Trend developed for its last generation of controllers and which gives considerable freedom to the control strategy designer. They do though feature some new control modules, including an integrator function and virtual heat meter, which together allow the monitoring of energy usage. And they have an improved optimum start/stop algorithm, which can maximise energy savings. An IQ411/412 strategy can incorporate a large number of individual control modules and up to 300 sequence steps, enough to satisfy the most sophisticated applications.
The IQ411 and 412 have a multitude of potential applications. By providing small ‘pockets’ of distributed intelligence around a building they represent a cost-effective means of achieving advanced control of a variety of heating, ventilation and air conditioning plant, as well as room-by-room or zone control. They could also provide all the control and monitoring necessary in premises where the building services are very limited – eg, just a boiler and a radiator circuit – such as a GP surgery, post office or small primary school.