Introduction PLAYING NICE: HVAC AND LIGHTING CONTROLS INTEGRATION. Why should I care? Background Integration VAV box Occ sensor

Transcription

1 PLAYING NICE: HVAC AND LIGHTING CONTROLS INTEGRATION Lyn Gomes, PE, LEED AP kw Engineering Introduction 2 Why should I care? Background Integration VAV box Occ sensor 4 methods for integration Points of failure Case study Final thoughts kw Engineering

2 Why should I care? 3 Poor implementation of the integration and Cx : MISERY Time consuming callbacks Benefits may never be realized May result in no energy savings Money spent goes down the drain Don t underestimate the effort! You must have a reason 4 Why? Data? Energy efficiency? Additional functionality? Integration for integration s sake is a bad idea kw Engineering

3 System Architecture Layers Remote Access Alarms Browser Based Monitoring and Control Enterprise Applications Building Operations Center Cal/Dispatch Center Reporting/Scheduling $$$ HARD WAN LAN Graphical User Interface Network Tools Diagnostics Web Interface Internet/VPN/Frame Relay Firewall Gateway to proprietary/ legacy systems IP-852 Router or obix XML Server or Web Server MONEY IP/Ethernet COMPLEXITY LON Device Network Standard Network Variables Exchanged Between Devices and to PC, Web, Remote Access $$ NOT AS HARD Source: Ron Bernstein, RBCG Consulting used with permission. One bite at a time 6 Our time is limited HVAC and lighting control system integration for occupancy-based demand controlled ventilation (DCV) Required by code Real-life examples kw Engineering

4 Why consider integration? 7 Code requires occupancy based demand control of lights and HVAC (in certain space types) Title 24 sec c.3 Owners desire energy savings Pushed by manufacturers, ESCOs, utilities But Lightning pace of lighting controls industry Issues with the current design phase approach leads to finger pointing & hiccups Construction phase coordination difficult Lighting controls are uncharted territory for many electrical contractors What is a VAV box? 8 kw Engineering

5 VAV box controller 9 Occupancy sensor load control Line Voltage Low Voltage Images courtesy of WattStopper kw Engineering

6 Occupancy Sensors PIR (Passive InfraRed) Ultrasonic Human hearing: 20Hz 20kHz Ultrasonic: >34kHz Microphonic Dual Technology Four methods Aux Relay within Occupancy Sensor 2. External Aux Relay 3. Separate occupancy sensor 4. BMS/Lighting Control System Integration 5. Others? kw Engineering

7 1. Aux Relay within Occupancy Sensor 13 Low or line voltage sensors only!!!! Responsibilities must be clearly defined Requires coordination in ALL phases How is occupancy status transmitted? How many sensors in the space? How many ways can it fail? 14 Low Voltage Occ Sensor 1 Load Junction Box Aux Relay Connection 2 Points of Failure VAV Controller and misc Controller 4 3 kw Engineering

8 2. External Auxiliary Relay 15 DDC Occupancy sensor plus: Auxiliary isolated relay device, or Auxiliary power pack EE/LC specs components Best value to Owner Status? Multiple sensors? External Aux Relay 16 kw Engineering

9 17 How many ways can it fail? 1 Lighting occupancy sensor 2 Room controller 3 Network Bridge HVAC integration relay Separate occupancy sensor 18 Dedicated occ sensor for VAV box Separate occ sensor for lighting Architect: Two occupancy sensors is ugly Owner: It s more to maintain Mechanical contractor may not understand how to install/adjust Responsibilities clearly defined Must be spec d separately (usu in ) Mechengineer know about Occsensors? It s usually Sparky territory kw Engineering

10 How many ways can it fail? 19 Lighting occupancy sensor Room controller Network Bridge HVAC occupancy sensor BMS/LCS Integration 20 Burden/responsibility shifts to contractor LOTS OF COORDINATION ME and EE GC, & (Mech, Controls, Elect) Subcontractors Specify very carefully! Coordination table Fully networked lighting control system BOTH control specs must include integration ( and ) Include time in your budget for coordination Difficult for maintenance Don t forget about IT/networking! Status? Multiple sensors are easier kw Engineering

11 Case Study: Data Integration 21 Doing Integration Right 22 How to do it wrong: Know whyyou re doing it Investigate capabilities of the system PICS Technical Bulletin IOM (aka O&M Manual) Describe responsibilities Details Specs Describe control sequences * PICS = Protocol Implementation Conformance Statement kw Engineering

12 Control System Coordination Table 23 Sequences 24 Standard VAV dual max sequence Explicit time delay Coordinate with lighting, where applicable Additional time delay may be appropriate Which occsensors send the signal? Easy for an office or conference room Harder for a large assembly space Temp setbacks in the Goldilocks Zone Risk losing control 2 deg F is typical Pre-occupancy Purge Mode Minimum airflow when unoccupied Suppress demand? Off-hour trigger exemption kw Engineering

13 How many ways can it fail? 25 Lighting occupancy sensor Room controller 5 Network Bridge VAV Controller and misc Controller BACNet Module 10 VRF Systems 26 Need a BACnet card! Optional equipment for most manufacturers Must be done through the BMS Integration not always necessary Status could be routed to nearby controller BMS then commands VRF unit Beware of input capability Modulate OA kw Engineering

14 27 Case Study Design Design showed no details of integration with vague sequences (Integration not worked out in design) No details = issue gets pushed to construction Integration details still unknown * Cx Role: design review and coordinator kw Engineering

15 Addendum Issues pushed to design integration meeting Issue not resolved in integration meeting because too many other issues to resolve and outsourcing responsibility to controls contractor Issue pushed to submittals Submittals Issue not resolved in submittal too difficult to coordinate different contractors Cx review identified issues Controls see lighting Electrical see controls Contractual issues! kw Engineering

16 Mechanical Controls Submittal 31 Lighting Control System Submittal 32 kw Engineering

17 Height of Construction 33 Contractor, Cx, Owner forced cooperation with Electrical Sub Contractor: We have an issue You need to fix it We will check your work Cx: We will test your work Call in favors to lighting supplier Owner: You work for us Listen to Contractor and kw It got built! Two different kinds of integration: Network Auxiliary relay Results: it works! Adjustments Pre-testing Adjustments Final testing kw Engineering

18 What can go wrong? 35 Applied to inappropriate spaces Or-equal submittal notcoordinated with mechanical (or shared with CxP!!) Crappy sequences Lack of coordination Lack of knowledge Lack of clear responsibility/ies Network latency Expectations not met Or-Equal lighting & HVAC control systems Incomplete integration Incomplete Cx design/build/post-occ What s next? 36 Wireless communication Addressable systems VRFs! kw Engineering

19 Other considerations 37 Owner s maintenance TRUMPs all No energy savings will be realized if it is not programmed or maintained, or if it is disabled Lighting control systems are not or equals Manufacturers report occupancy status differently Sequences must be written differently Thanks for watching! 38 Know what you want Put in the effort Simpler is better Coordinate Maintainability is crucial Test together Lyn Gomes, PE, CCP, LEED AP, CLCATT kw Engineering lgomes@kw-engineering.com kw Engineering

20 Integration and Sequencing Questions 41 How quickly does the HVAC system know when the room is vacant/occupied? How fast does it need to know and respond Is the time it takes for the HVAC system to go vacant the same as the lighting system? Are they on separate timers or subsequent timers What tools are in place to troubleshoot the occupancy state? If the occupancy/hvac system isn t working, who do you call to fix it, the lighting shop, the HVAC shop, or the control engineers? Make Decisions Early and not later 42 Figure out how you will control occupancy based HVAC at the start of the project Don t do it across multiple projects. Define how many lighting controls or metrics you need to manipulate or track centrally Define and assign responsibility for the commissioning and integration of all those systems and solutions. How much will be tested? 10% 100% kw Engineering

21 45 How is your maintenance department set up? (Who will own it?) Maintenance - Physical Stuff Lighting lights, switches HVAC VAV controllers, thermostats, Air Handlers, etc Control System Hardware- controls infrastructure IT Security Network Architecture and infrastructure Security Rules Data shop Data Metering + integration with other energy metering Data Historian Energy Manager What is their role in your org? How to prevent a maintenance nightmare 46 Say something goes wrong: identifying the problem and fixing the issue should NOTrequire teamwork Problems should be solved by one team, one trade No finger pointing! Ensure issues can be resolved by existing staff CxPs: frank discussion of staff s strengths, time commitments Owners: If new expertise is needed, find it. kw Engineering