BACnet PTEC Controller Dual Duct 2 AVS - VAV Two Inlet Sensors with Optional Reheat, Application 6667 Application Note 140-1115 2017-05-31 Building Technologies
Table of Contents Overview ........................................................................................................................5 BACnet .........................................................................................................................8 Hardware Inputs ..............................................................................................................8 Room Unit Identification ................................................................................
Application 6667 Point Database................................................................................ 25 4 Siemens Industry, Inc.
Overview BACnet Overview NOTE: For information on applications with Firmware Revision B x40 or earlier, see InfoLink and/or Asset Portal for documentation. In Application 6667, the controller modulates two inlet damper actuators–one for the hot duct and one for the cold duct. In cooling mode, the controller modulates the cold duct damper to maintain the room temperature setpoint and modulates the hot duct damper to ensure minimum airflow.
Overview BACnet Application 6667 Control Diagram. 6 Siemens Industry, Inc.
Overview BACnet Application 6667 Control Schedule. NOTES: 1. See Control Temperature Setpoints. 2. See Heating/Cooling Switchover. 3. The reheat can be either a modulating valve or time modulated electric reheat. See Optional Auxiliary Heat. 4. The reheat can be sequenced to operate either in series or in parallel with the hot duct damper. It is shown in series. See Sequencing Logic. 5.
Overview BACnet BACnet The controller communicates using BACnet MS/TP protocol for open communications on BACnet MS/TP networks.
Overview Hardware Outputs l For Digital Room Units (Firmware Revision 26 and later) – The revision number displays for 5 seconds when the room unit is first powered up or when a laptop is disconnected. These room units will continue to display and update the room temperature sensor values when a laptop is connected.
Sequence of Operation Control Temperature Setpoints Sequence of Operation The following paragraphs present the sequence of operation for Application 6667 -VAV Two Inlet Sensors with Optional Reheat. Control Temperature Setpoints This application has a number of different room temperature setpoints (DAY HTG STPT, NGT CLG STPT, RM STPT DIAL, etc.). The application actually controls using the CTL STPT.
Sequence of Operation Control Temperature Setpoints CTL STPT Using Standard/Absolute Mode (Digital Room Unit, Revision 26 and later) Digital Room Unit (2200/2300 Series Firmware Revision 26 and later) For all new digital room units, the value displayed and reported by the room unit is linked to the current heat/cool mode. When the mode changes, the value is automatically updated based on the new heat/cool mode.
Sequence of Operation Control Temperature Setpoints CTL STPT Using Standard/Absolute Mode (Analog or Digital Room Unit) Analog (Series 1000) or Digital Room Units (Firmware Revision 25 or earlier) NOTE: 2200/2300 digital room units with Firmware Revision 25 or earlier are only compatible with standard room unit functionality (no warmer/cooler). When STPT SPAN is set to 0, CLT STPT is set based on the value of the setpoint dial and the setpoint deadband.
Sequence of Operation Heating/Cooling Switchover The full range of the analog room unit slider will be mapped to a range of minimum setpoint value to maximum setpoint value. CTL STPT is set equal to RM STPT DIAL. The values for RM STPT MIN and RM STPT MAX will be applied to limit RM STPT DIAL before it is copied into CTL STPT. Example in Cooling Mode If the STPT SPAN is set to 2.0 degrees, and the DAY CLG STPT is 76°F, the room unit slider will adjust the cooling setpoint from 74°F to 78°F.
Sequence of Operation Heating/Cooling Switchover Cooling switchover point is equal to RM STPT DIAL – DAY HTG STPT + DAY CLG STPT Example DAY CLG STPT = 74 and DAY HTG STPT = 70 In cooling mode, when the user adjusts the setpoint value on the room unit to 76, the heating switchover point will equal 72 - SWITCH DBAND.
Sequence of Operation Room Temperature, Room Temperature Offset and CTL TEMP Heating/Cooling Switchover Using Warmer/Cooler Mode (Analog Room Unit) Analog Room Unit (Series 1000) The RM STPT DIAL will display the current temperature setpoint based on a plus or minus position or increment entered by the user at the room unit. The amount of offset that can be entered with the analog room unit is limited to a value of minus STPT SPAN to plus STPT SPAN.
Sequence of Operation Ventilation Demand Minimum Ventilation Demand Minimum This VAV application has the ability to adjust the minimum flow setpoint for varying ventilation needs during occupied times. This may be done internally on controllers with PPCL, or externally via IAQ or DCV programs in a field panel.
Sequence of Operation Cooling Operation CLG FLOW MAX. During occupancy in heating mode, the cooling flow loop insures that sufficient flow from the dual duct unit does not drop below the larger of TOT FLOW MIN or VENT DMD MIN. During unoccupied periods in cooling mode, the cooling flow loop maintains the cold duct airflow between 0 cfm and the value of CLG FLOW MAX.
Sequence of Operation Optional Auxiliary Heat so that the total flow is equal to, or greater than, NGT FLOW MIN, the cooling flow damper will open to make up the difference. See Optional Auxiliary Heat [➙ 18] for more information. Optional Auxiliary Heat If AUX HTG USED = YES, this application also controls auxiliary heat. The value of AUX HTG TYPE indicates the type of auxiliary heat control. If AUX HTG USED = NO, no auxiliary heat is used.
Sequence of Operation Calibration Calibration Calibration of the controller’s internal air velocity sensor(s) is periodically required to maintain accurate air velocity readings. CAL SETUP is set with the desired calibration option during controller startup. Depending on the value of CAL SETUP, calibration may be set to take place automatically or manually. If CAL AIR = YES, calibration is in progress. Calibration of the valve is not affected by the presence of Autozero Modules.
Sequence of Operation Auto Discovery SENSOR SEL Value * (additive) Description (include values to enable feature) 1 Select Digital Room Unit (for temperature sensing and setpoint dial) 2 Relative Humidity (RH) sensing 4 CO2 sensing 8 If short board: 100K Ω thermistor on AI 3 (else input is 10K Ω) If long board: 100K Ω thermistor on AI 5 (else input is 10K Ω) 16 Long board only: 100K Ω thermistor on AI 4 (else input is 10K Ω) Room CO2 RM CO2 displays the CO 2 value in units of parts-per-million
Sequence of Operation Fail Mode Operation Fail Mode Operation If either of the air velocity sensor points, CLG VOLUME or HTG VOLUME is failed, damper control depends on the status of HEAT.COOL. l If HEAT.COOL reads HEAT, the following occurs: – HTG DMP CMD is set equal to the heating flow setpoint, HTG FLO STPT, – CLG DMP CMD is set equal to 100% minus HTG FLO STPT. This causes the hot duct and the cold duct dampers to be controlled as pressure dependent dampers by the heating temperature loop. l If HEAT.
Sequence of Operation Wiring Diagrams Wiring Diagrams CAUTION The controller’s DOs control 24 Vac loads only. The maximum rating is 12 VA for each DO.
Sequence of Operation Wiring Diagrams Applications 6665, 6666, 6667, and 6668 with Hot Water Reheat. 23 Siemens Industry, Inc.
Sequence of Operation Wiring Diagrams Applications 6665, 6666, 6667, and 6668 with Electric Auxiliary Reheat. 24 Siemens Industry, Inc.
Application 6667 Point Database Application 6667 Point Database Object Type a) Object Instance (Point Number) Object Name (Descriptor) Factory Default (SI Units) b) Eng Units (SI Units) Range Active Text Inactive Text AO 1 CTLR ADDRESS 255 -- 0-255 -- -- AO 2 APPLICATION 6693 -- 0-32767 -- -- AI {04} ROOM TEMP 74.0 (23.44888) DEG F (DEG C) 48-111.75 -- -- BO {05} HEAT.COOL COOL -- Binary HEAT COOL AO 6 DAY CLG STPT 74.0 (23.44888) DEG F (DEG C) 48-111.
Application 6667 Point Database Object Type a) Object Instance (Point Number) Object Name (Descriptor) Factory Default (SI Units) b) Eng Units (SI Units) Range Active Text Inactive Text AI {30} HTG VOLUME 0 (0.0) CFM ( LPS) 0-131068 -- -- AO {32} CLG FLOW MAX 2200 (1038.18) CFM ( LPS) 0-131068 -- -- AO {33} TOT FLOW MIN 220 (103.818) CFM ( LPS) 0-131068 -- -- AO {34} HTG FLOW MAX 2200 (1038.18) CFM ( LPS) 0-131068 -- -- AI {35} CLG VOLUME 0 (0.
Application 6667 Point Database Object Type a) Object Instance (Point Number) Object Name (Descriptor) Factory Default (SI Units) b) Eng Units (SI Units) Range Active Text Inactive Text AO 67 HTG P GAIN 10.0 (18.0) -- 0-63.75 -- -- AO 68 HTG I GAIN 0.012 (0.0216) -- 0-1.023 -- -- AO 69 HTG D GAIN 0 (0.0) -- 0-510 -- -- AO 70 HTG BIAS 50 PCT 0-102 -- -- AO 71 CLGFLO PGAIN 0 -- 0-51.15 -- -- AO 72 CLGFLO IGAIN 0.018 -- 0-1.
Application 6667 Point Database Object Type a) Object Instance (Point Number) Object Name (Descriptor) Factory Default (SI Units) b) Eng Units (SI Units) Range Active Text Inactive Text AO {103} AOV 2 0 VOLTS 0-10.23 -- -- AO {104} AOV 3 0 VOLTS 0-10.23 -- -- AI {105} AI 3 0 PCT 0-102 -- -- AI {106} AI 4 0 PCT 0-102 -- -- AO {107} RMTMP OFFSET 0.0 (0.0) DEG F (DEG C) -31.
Issued by Siemens Industry, Inc. Building Technologies Division 1000 Deerfield Pkwy Buffalo Grove IL 60089 USA Tel. +1 847-215-1000 Document ID 140-1115 Edition 2017-05-31 © 2017 Copyright Siemens Industry, Inc. Technical specifications and availability subject to change without notice.
