The problem sequencing solves
When each compressor uses its own pressure setting, machines overlap, run partly loaded or unloaded and widen the pressure band. A sequencer coordinates them against one pressure target and rotates duty so wear is shared.
What a sequencer does
Typical functions:
- Starts and stops compressors in response to demand
- Keeps the pressure within a narrower band
- Rotates duty between machines
- Handles standby and fault changeover
- Reports running data and alarms
What to consider
Points to settle before choosing:
- How many machines and whether they are different sizes or types
- Whether variable-speed machines are included
- The pressure target and the allowed band
- How it connects to each compressor's controller
- Who will maintain it and how alarms will be handled
Not a cure for system problems
A sequencer cannot fix leakage, restricted piping or under-sized storage. Measure the system first so the sequencer is set up around real demand.
What to prepare
Information that helps us advise:
- Number, make, model and size of the compressors
- Current controllers and how they are connected
- Pressure settings and the lowest pressure the process needs
- Demand pattern across shifts and any known problems
Frequently asked questions
Do I need a sequencer for two compressors?
Not always, but overlapping pressure settings can waste energy. A well-set cascade or a simple sequencer may be enough.
Can it work with different brands of compressors?
Often yes, depending on the interfaces available. We confirm the connection method for each machine.
Does a sequencer reduce the pressure I run at?
It allows a narrower band, which can allow a lower average pressure, provided the process needs are met and it is verified.
Field guide
Sequencers: making several compressors behave as one
Where two or more compressors feed the same system, each machine's own pressure switch tends to fight the others: several run part-loaded at once, pressure swings and energy is wasted. A sequencer decides which machines run, in what order, and holds the whole system in a single pressure band.
What a sequencer does
- Starts only as many machines as demand needs, in a set or rotating order.
- Keeps one machine (often a VSD) trimming while the others run fully loaded or stopped.
- Equalises running hours by rotating the lead machine.
- Brings in a standby automatically if a running machine trips.
- Lowers the overall pressure band, because machines no longer need staggered settings.
Signs a site needs one
- Two or more compressors often running unloaded at the same time.
- Pressure swinging widely through the day.
- Machines' pressure settings staggered by a bar or more to stop them fighting.
- One machine with far more hours than the others.
Before fitting
Measure demand over a typical week, check each compressor's controller can accept remote load and start signals, and make sure the receiver volume and pipework let the sequencer see a stable system pressure. A sequencer cannot fix a pressure drop in the pipework; it only controls the machines.
What to send for a quotation
- Make, model and serial number of every compressor and dryer in the station.
- Running hours and a typical week of operation (shifts, weekends).
- Current pressure settings and controller type on each machine.
- Any alarm or fault history you have.
Send it through find my part or the spare parts enquiry, or call +91 99590 60718 or +91 92468 88812.