A control point is any single value a building automation system reads or writes — a temperature input, a valve command, a fan status, an alarm. Points come in four types: analog and binary, input and output. The points list, which enumerates every one, is the most important document in a controls project: it defines what the system can see and do, and it drives the controller sizing, the wiring, the cost, and the bid.
Think of a point as one piece of information flowing in or out of the control system. The space temperature is a point. The command to open a valve is a point. The status telling you a fan is running is a point. An alarm is a point. Everything the system knows and everything it does is a collection of points.
Count the points and you have measured the system — its size, its capability, and much of its cost.
Points are categorized two ways. Input vs output: an input is information coming in (a sensor reading, a status); an output is a command going out (open a valve, start a fan). Analog vs binary: analog is a continuous value (a temperature, a valve position from 0 to 100%); binary is on/off (a fan running or not, a command to start or stop).
That gives four types — analog input (AI), analog output (AO), binary input (BI), binary output (BO). A space temperature is an AI; a modulating valve command is an AO; a fan status is a BI; a fan start command is a BO.
The points list enumerates every point in the project, typed, named, and associated with its equipment. It is built during design and is the specification the controls contractor bids and builds to. A complete points list means the bid covers everything; a thin one means scope gaps surface during commissioning as “that wasn’t included.”
For an owner, insisting on a thorough points list at design time is one of the best protections against controls surprises. See the sequence of operations, which the points list works hand in hand with.
Points drive controller sizing (controllers have a fixed number of input/output terminals), wiring (each hard-wired point is a run of cable to land and label), and labor (each point is configured and checked). More points means more capability but more cost — so the points list is also where value decisions get made.
This is why two controls bids can differ widely: they may be pricing different point counts. Comparing bids without comparing points lists is comparing nothing.
Not every point is a physical wire. Hard points connect to real sensors and devices. Soft or virtual points are values that live in software — calculated values, setpoints, schedules, and data read from equipment over a communication protocol like BACnet or Modbus rather than hard-wired.
Pulling data over an open protocol can replace dozens of hard-wired points with network points, which lowers wiring cost and is part of why open, communicating equipment is efficient to integrate. See BACnet vs Modbus.
A control point is any single value the system reads or writes — a temperature reading, a valve command, a fan status, an alarm. Points are the units that make up a control system; counting them measures the system’s size, capability, and much of its cost.
Analog input (a continuous reading like temperature), analog output (a modulating command like valve position), binary input (an on/off status like fan running), and binary output (an on/off command like fan start). Inputs bring information in; outputs send commands out.
The points list enumerates every point in the project and is the specification the controls contractor bids and builds to. A complete list means the bid covers everything; gaps surface at commissioning as excluded scope. It also drives controller sizing, wiring, and cost.
Hard points connect to physical sensors and devices by wire. Soft or virtual points live in software — calculated values, setpoints, schedules, or data read from equipment over a protocol like BACnet or Modbus. Network points can replace many hard-wired points, lowering cost.
Suncoast Cold Systems installs, wires, and configures the HVAC controls integral to the mechanical systems we provide — and specifies open protocols (BACnet, Modbus, open supervisory platforms) so you own your building’s controls and data, with no proprietary dealer lock-in. Where a project calls for certified systems integration, we coordinate it within one accountable mechanical scope. Licensed Florida Class A Air Conditioning Contractor (FL #CAC1824642).