The Sequencer group contains the MSC 01 through MSC 12 modules for terminal unit control, Sequencer 01 through Sequencer 16 for simple staging, and the Global Sequencer module for custom applications. The following table provides a comparison of the three sequencers.
Sequencer Feature | Multi-Stage Controller (MSC) | Sequencer 01 through Sequencer 16 | Global Sequencer | Previous DX Sequencer |
---|---|---|---|---|
System |
Electric Heaters HVAC |
Chillers Boilers |
Chillers Boilers Pumps Electric Heaters Single Oil Pumps |
Chillers Boilers Pumps Electric Heaters |
DX Replacement Compatible |
No | No | Yes | N/A |
System Selection Tree Creation |
VAV, Air Handling Units, Fan Coil, Unit Ventilators, Heat Pumps, by Output Controller column, or by Logic View palette | Simple Central Plant, Central Heating Plant, Central Cooling Plant, by Output Controller column, or by Logic View palette | Not in selection trees created through Output Controller column or Logic view palette | N/A |
Upfront Configuration Process |
Details Panel | Details Panel | Wizard, Details Panel | Details Panel |
Number of Devices |
12 | 16 | 16 | 8 (16) |
Input |
0–100%
Upstream controller is expected to be a PID. |
Scalable, default is 0–100% |
Scalable, default is 0–100% |
0–100% |
Mode |
Yes PMAC varies the on and off times as well as the cycle time. It generates a pulse train based on the vernier control signal. A pulse train is comprised of a sequence of on and off states. These on and off states always respect the Minimum on and Minimum off times. |
Rank
Provides intelligent rotation of the start and stop order of the outputs based on the rank and the device status. Runtime and Startup count can be input to rank. It has potential to support Step Mode, Equal runtime, and Equal Startup. The order is calculated dynamically. |
Step Mode: The order is decided according to Device number. Sequential Mode: First On, First Off. Equal Runtime: 1 Lowest runtime device is First On Last Off; highest runtime device is Last On First Off. Runtimes are external input. The order is calculated dynamically. Binary Code: Sequence according to a binary code principle. Equal Startup: 2 Lowest Startup count device is First On Last Off; Highest Startup count device is Last On First Off. Startups are external input. The order is calculated dynamically. |
Step Mode: The order is decided according to Device number. Sequential Mode: First On, First Off. Equal runtime: Lowest runtime device is First On Last Off, Highest runtime device is Last On First Off. Runtimes are calculated in primitive. The order is calculated dynamically. Binary Code: Sequence according to a binary code principle. |
Proactive |
No When proactive is true, one stage is always on. |
Yes | Yes | Yes |
Capacity/Make Limits |
Capacity
Set per each stage |
Make Limits
Set per each stage |
Capacity
Make Limits Make Limits are calculated when Calculate Make-Break Limits is True. Set per each Stage. Binary Code uses only Capacity. |
Capacity
Set per each stage |
Differential (Hysteresis)/Break Limits |
Staging Hysteresis
1 set per all stages |
Break Limits
Set per each stage |
Differential Break Limits Break Limits are calculated when Calculate Make-Break Limits is True. Move Set per each Stage under Break Limits. |
Differential 1 set per all stages |
Instant Shutdown |
Yes | Yes |
Yes Instant Shutdown Delay is used to control the rate at which the devices turn off. |
Yes Fast Step Down is used to control the rate at which the devices turn off. |
Device Enable |
Yes | Yes | Yes | Yes |
Grouping |
Yes Device First Of - This specifies how many devices are in the group where this device is the first of the group. This device and the following (value – 1) devices are grouped together for control. The Device First Of property for the dependent devices of this group are ignored. |
No |
Yes Device First Of – This specifies how many devices are in the group where this device is the first Of the group. This device and the following (value – 1) devices are grouped together for control. The Device First Of property for the dependent devices of this group are ignored. |
Yes Set-Stage |
Invert Stage in Set |
Yes | No | Yes | Yes |
Equal Runtime Within Sets |
No | No |
Yes Equal Runtime mode only |
No |
Rotate Now |
Yes | Yes |
Yes The Rotate Now Delay is used by the Rotate Now feature to turn new devices on before turning previously running devices off. |
No |
Force Upstage |
No | No | Yes | No |
Force Downstage |
No | No | Yes | No |
Inter-Stage On Delay/Inter-Stage Off Delay |
No | 1 set per all stages | Set per each stage | 1 set per all stages |
Stabilize On Delay/Stabilize Off Delay |
No | No | Set per each stage | No |
Minimum On Time/Minimum Off Time |
1 set per all devices | 1 set per all stages | Set per each stage | 1 set per all stages |
First Set On Delay |
No | No | Yes | Yes |
Vernier Control |
Yes | No | Yes
An analog output of 0 to 100 that indicates the required percentage of the currently modulated device required to meet the required capacity. The remaining output is rescaled from 0 to100%. |
No |
Status Displayed |
Vernier Out Active Stage Count Percent Capacity Enabled Percent Request Max Capacity Fraction Pulsed Device |
Operating State Interstage Timing Current Stage |
Vernier Out Operating State Current Stage Remaining Next Device to Start / Stop Interstage Time Remaining Stabilize Time Remaining Minimum On/Off Time n Remaining |
OUT: = input OUTS: Total of the Capacity of Active device. OUTD: =OUTS-OUT MCSn: This attribute is On when an interstage timer is counting. |
Pump Down (Solenoid Valve Out) |
No | No | Yes | No |
Single Oil Pump |
No | No | Yes
Device 1 or Oil Pump Output |
No |