Power: energy management

BMS bureau services

At our office in Bristol we operate a Building Management System Bureau for the monitoring and control of client buildings. To date we have operated this service using the following systems:-

	Satchwell BAS 2000 and 2800+
	BICC Andover Infinity SX8000
	SIEBE Robertshaw FMS/FI
	Cylon Controls
	Johnson Metasys
	Landis and Gyr Visonik
	Honeywell EMS/Excel 500
	Trend Control Systems
	Barber Coleman Network 8000
	Robertshaw DMS 35 and 350

The BMS Bureau provides five key services:- Alarm Monitoring, Operational Support, Energy Enhancement, Trend Logging and Activity Reporting.

Alarm Monitoring

The alarms generated by a BMS can be ranked into two priorities

Critical - those alarms which if not acted upon would probably lead to a failure to deliver adequate environmental conditioning. Typical of such alarms are:-

	boiler lockout
	chiller failure
	fan failure
	duty pump failure
	pressurisation unit failure
	fire alarm
	non-critical - those alarms of a more advisory nature.

Typical of such alarms are:

	space temperature too high
	filter dirty
	pump runs hours above maintenance target
	pump auto changeover initiated

The procedure adopted to handle these alarms depends upon the agreed Service Level Agreement (SLA) targets to be achieved. Typically this is to respond to all critical alarms within 15 minutes of their initiation during a time frame of 8.00 a.m to 6.00 p.m. Monday to Friday.

Operational Support

Many of our client's buildings have user requirements that can vary on a day to day basis. Our Operational Support package provides the on-site Facilities Manager direct contact with our BMS Bureau Help Desk. With this support we can respond to user needs through such things as adjustment of:-

	control conditions/set points
	adjustment of occupancy schedules for overtime, evening events, special leave periods, e.g. Queens birtheday, and Bank Holidays
	initiation of British Summertime changeover (if appropriate)
	manual control of specific plant items such as fresh air dampers
	advice on use of local BMS operation interface to interrogate system
	assistance with environmental control problems which cannot be resolved by local operator.

In addition, this package allows for liaison with contractors in order to operate plant out of occupation time for maintenance purposes.

Energy Enhancement

The objective of energy enhancement is to optimise building control such that energy demands and consumption are minimised. Work under the banner of energy enhancement can be extremely beneficial in terms of reducing energy costs, but is very time intensive.

We would normally commit ourselves to auditing the software over a 12 month period, but would implement strategy improvements as we find opportunities. However, it is often only through monitoring system performance over a full year that all opportunities are uncovered. Consequently, it may not be until the second year that all benefits are identified, and routines 'fine-tuned'.

Within this activity we review, on a regular basis, the operational performance of all control algorithms for maximum energy control. These reviews are carried out via the logging of system variables, day to day reviews of HVAC system control and feedback from site representatives and maintenance contractors.

Trend Logging

BMS facilities provide an ideal opportunity to check that time schedules and heating/cooling optimisers are working correctly through the trend logging of key operational parameters such as boiler flow temperatures, cooling water supply temperatures and where suitable meters are fitted, utility supply demands.

On a monthly basis the operation of the boilers and chillers are checked. This is achieved through monitoring of flow water temperatures. Every month a graph is provided of flow temperature against time. This is examined to ensure that the plant was disabled during evenings and weekends.

In addition, where utility meters are connected to the BMS, meter readings are logged on a weekly basis to obtain consumption data. In addition, half hour logging of these meters is carried out on a regular basis and a graphical print out provided of consumption over a 7 day period.

Activity Reporting

All activities undertaken by the BMS Bureau are recorded in an MS Access Database on a site by site basis. The activity log records the following:

	area affected
	priority, e.g. immediate, next day, next week, etc.
	originator, e.g. alarm, site request, maintenance contractor, etc.
	alarm or request description
	action taken
	date alarm cleared of action indicated