introduction...4. bms/lcs integration burden/responsibility shifts to contractor lots of...

10/24/2018

© kW Engineering 2018 1

PLAYING NICE:

HVAC AND

LIGHTING

CONTROLS

INTEGRATION

Lyn Gomes, PE, LEED APkW Engineering

www.kw-engineering.com

Introduction

� Why should I care?

� Background

� Integration

� VAV box

� Occ sensor

� 4 methods for integration

� Points of failure

� Case study

� Final thoughts

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Why should I care?

� 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!

3

You must have a reason

� Why?

� Data?

� Energy

efficiency?

� Additional

functionality?

� Integration for

integration’s sake

is a bad idea

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IP/EthernetIP-852 Router or oBIX XML Server or Web Server

Remote Access EmailAlarmsBrowser BasedMonitoring and Control

Standard Network Variables Exchanged Between Devices and to PC, Web, Remote Access

Graphical User Interface Network Tools DiagnosticsWeb Interface

LON

Device Network

LAN

Internet/VPN/Frame Relay

Enterprise Applications Building Operations Center Cal/Dispatch Center Reporting/Scheduling

WAN

Gateway to proprietary/

legacy systems

Firewall

System Architecture Layers

Source: Ron Bernstein, RBCG Consulting – used with permission.

MONEY

$$$

$$

COMPLEXITY

HARD

NOT AS HARD

One bite at a time…

� Our time is limited

� HVAC and lighting

control system

integration for

occupancy-based demand controlled ventilation (DCV)

� Required by code

� Real-life examples

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Why consider integration?

� Code requires occupancy based demand control of lights and HVAC (in certain space types)

� Title 24 sec 120.1.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

7

What is a VAV box?8

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VAV box controller9

Occupancy sensor load control

� Line Voltage

� Low Voltage

Images courtesy of WattStopper

10/24/2018


� PIR (Passive InfraRed)

� Ultrasonic

� Human hearing: 20Hz –

20kHz

� Ultrasonic: >34kHz

� Microphonic

� Dual Technology

Occupancy Sensors

Four methods

1. Aux Relay within Occupancy Sensor

2. External Aux Relay

3. Separate occupancy sensor

4. BMS/Lighting Control System Integration

5. Others?

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1. Aux Relay within Occupancy Sensor

� 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?

13

How many ways can it fail?14

1

2

3

4

Points of Failure

Low Voltage Occ Sensor

Load Junction

Box

ControllerVAV Controller and misc

Aux Relay Connection

10/24/2018


2. External Auxiliary Relay

� DDC Occupancy sensor

plus:

� “Auxiliary isolated relay

device”, or

� “Auxiliary power pack”

� EE/LC specs components

� Best value to Owner

� Status? Multiple sensors?

15

External Aux Relay16

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12

3

4

5

6

7

8

Lighting occupancy sensorRoom controller

Network Bridge

HVAC integration relay

3. Separate occupancy sensor

� 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 250000)

� Mech engineer know about Occ sensors?

� It’s usually “Sparky” territory

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How many ways can it fail?

19

1

2

34


Network Bridge

HVAC occupancy sensor

4. BMS/LCS Integration

� 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 (25 00 00 and 26 09 23)

� Include time in your budget for coordination

� Difficult for maintenance

� Don’t forget about IT/networking!

� Status?

� Multiple sensors are easier

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Case Study: Data Integration21

Doing Integration Right

� Know why you’re doing it

� Investigate capabilities of the system

� PICS

� Technical Bulletin

� IOM (aka O&M Manual)

� Describe responsibilities

� Details

� Specs

� Describe control sequences

22

How to do it wrong:

* PICS = Protocol Implementation Conformance Statement

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Control System Coordination Table23

Sequences

� “Standard” VAV dual max sequence

� Explicit time delay

� Coordinate with lighting, where applicable

� Additional time delay may be appropriate

� Which occ sensors 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

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1

2

3

4

56

7

8

9

10

11

12

13


Network Bridge

BACNet Module

ControllerVAV Controller and misc

VRF Systems

� 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

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Case Study

27

Design

1. 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

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Addendum…

2. 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

29

Submittals30

3. Issue not resolved in submittal – too difficult to coordinate

different contractors

� Cx review identified issues

� Controls – see lighting

� Electrical – see controls

� Contractual issues!

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Mechanical Controls Submittal31

Lighting Control System Submittal32

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Height of Construction

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

33

It got built!

5. Two different kinds of integration:

� Network

� Auxiliary relay

� Results: it works!

� Adjustments

� Pre-testing

� Adjustments

� Final testing

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What can go wrong?

� Applied to inappropriate spaces

� Or-equal submittal not coordinated 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

35

What’s next?

� Wireless communication

� Addressable systems

� VRFs!

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Other considerations

� 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

37

Thanks for watching!

� Know what you want

� Put in the effort

� Simpler is better

� Coordinate

� Maintainability is crucial

� Test together

38

Lyn Gomes,

PE, CCP, LEED AP, CLCATT

kW Engineering

[email protected]

10/24/2018


Integration and Sequencing Questions

� 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?

41

Make Decisions Early……and not later

� 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%

42

lgomes

Text Box

Extra slides (supplemental info)

10/24/2018


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?

45

How to prevent a maintenance nightmare

� Say something goes wrong:

� identifying the problem and fixing the issue should NOT require

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.

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introduction...4. bms/lcs integration burden/responsibility shifts to contractor lots of...

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