Mitsubishi Heavy Industries Technical Review Vol. 51 No. 2 (June 2014)35

Improvement of Remote Monitoring Servicefor Centrifugal Chiller Driving Situation

S a l e s D e pa r t m e n t
Air-Conditioning & Refrigeration
DivisionM a c h i n e r y, E q u i p m e n t & I n f r a s t r u c t u r e

In recent years, demand for energy-saving operation of individual centrifugal chillers has
been increasing in response to growing requests for the improvement of the energy-saving
characteristics of air conditioning facilities. For this reason, the capability of allowing customers tobe aware of the operating state of the chiller in real time remotely from their offices, headquarters
and other places has been an important need. In order to meet this requirement, Mitsubishi Heavy
Industries, Ltd. (MHI) has developed a chiller operating data browsing system that uses theubiquitous Internet environment. This paper presents the developed system.

|1. Introduction
Currently MHI offers remote chiller monitoring services using the public telephone network(MODEM (Modulator-Demodulator)) and an Internet line (web logger), but the use of an Internetline has been prevalent due to the requests of customers for real time monitoring and changes in thecommunication environment. In addition to monitoring the operating state of the chiller, demandfor proposals and support for the optimum operation of the chiller based on the collected data hasrecently been increasing.
As such, MHI has developed a chiller operating data browsing system named “CentrifugalChiller Club” that enables web-based remote monitoring in order to expand the services of themonitoring system through an Internet line (VPN (Virtual Private Network)). On this website,
customers can browse specifications, periodic reports and the maintenance history, in addition tothe operating data, of the chillers delivered by MHI.

|2. Features of product(1)

Browsable information
The “Centrifugal Chiller Club” web-based remote monitoring system offers customers aservice that enables not only the ability to browse the operating state of the chiller, but also
download periodic reports and review its maintenance status.
・ Awareness of operating state
Customers can check the start/stop state and the main temperature and pressure valuesof the chiller on the schematic diagram (Title figure) (Figure 1).
・ Periodic report
As shown in Figure 1, the operating data of the chiller are displayed in charts, and theaverage values for the day and data at any five time points are also indicated in the daily
report (Figure 2). Daily reports, weekly reports and monthly reports are available as periodicreports. The operating state can be summarized immediately because a report is createdautomatically on the day after the operating day for a daily report (Sunday or Monday eachweek for weekly reports and the 1st day of the month each month for monthly reports). The
daily report presents the COP (Coefficient Of Performance) and the load factor on a chart, in
addition to temperature and pressure values, and therefore changes in the operating load canbe easily reviewed.

Mitsubishi Heavy Industries Technical Review Vol. 51 No. 2 (June 2014)36

・

Maintenance state
Necessary maintenance items for the targeted chiller are shown in calendar form, andtherefore the maintenance execution history and the future plan can be checked at a glance(Figure 3).

Figure 1 Awareness of operating state

Figure 2

Periodic report (daily report)Operating data of the chiller are displayed in charts, and the average values ofthe day and data at any five time points are reported.

Figure 3 Maintenance calendar screen
Necessary maintenance items for the chiller are shown in calendar form, andtherefore the execution history and the future plan can be checked at a glance.

Mitsubishi Heavy Industries Technical Review Vol. 51 No. 2 (June 2014)
37(2)Communication structure of remote monitoring system
Operating data from each chiller are collected using a VPN environment on a dedicatedInternet line (Figure 4). The “Centrifugal Chiller Club” web-based remote monitoring system
can be browsed through the common Internet using an ID and a password issued to customers
individually.

Figure 4 Communication structure diagram of remote monitoring
This simplified diagram summarizes the communication structure between chillers and the monitoring site.

|3. Future prospects
MHI plans to not only propose and support the optimum operation of the chiller based on thedata collected through the “Centrifugal Chiller Club” web-based remote monitoring system, butalso use the data for the proposal of energy-saving measures and the support of the optimum
operation of the entire air conditioning system. In addition, MHI will disclose necessary
maintenance items for the long-term operation of chillers, thereby enabling the proposal of
long-term maintenance schedules to customers.