Hillview Animal Sanctuary
Hillview Animal Sanctuary in County Cork, Ireland is a rescue centre for cats and kittens. The sanctuary can have in the region of 100 cats in residence at any one time. Some of the cats that are taken in can be in a very poor condition and as such need “intensive care” facilities. With relevance to this application note is the need to know the enclosure(s) temperature of where the animal(s) in question are kept. The same is true for very young (orphaned) kittens that come in, they have specialised requirements too. For the purpose of the application note, young kittens cannot regulate their own body heat and should be ideally kept at a temperature of 26 degrees C.
24/7 Temperature Monitoring
The author with recently rescued “Marmalady”
Hillview Sanctuary for a long time had a need of being able to accurately monitor the temperature in the various enclosures were the cats are kept. This caused considerable problems since these enclosures are spread over an acre site. Long cable runs with all associated ohmic losses precluded the use of cheap and cheerful solutions where resistance values would have greatly influenced the readings at the monitoring point. (These solutions were tried but the errors could be in excess of 200%!) In addition, Hillview uses volunteers to help with the day to day running of the sanctuary and any system would have to be very simple and robust to withstand the rigours of day-to-day use. This is a 24/7/365 operation.
Equipment Requirements
The solution for Hillview Sanctuary needed to meet the following criteria:
- System must be able to take long cable runs without undue errors being introduced
- System must be simple to operate and should be able to run totally unattended
- The solution should not require a PC to be running on a 24 hour basis
- Any sensors should be able to stand repeated spraying with disinfectant. (Virkon C)
- System should be able to hold values during power cuts (common in this area)
- Alarm thresholds should be configurable to cope with varying requirements
- System should be modular and able to cope with expansion/reconfiguration
- Ideally, monitored data should be able to be interrogated remote from the site. (Modem)
- Being a charity, any solution should be cost effective, as funds are very tight
The Chosen Solution
In-depth investigation into these requirements lead to the Pico Technology EnviroMon system which indeed met all of the above criteria. Key requirements like the sensors resistance against chemicals are met since the thermistors are enclosed in stainless steel.
The actual converters in use are protected to IP 65 and as such can tolerate the occasional misting with Virkon C. Perhaps most importantly the long cable runs are not a problem as digital signals are transferred across the network.
New converters and sensors can be added, or removed, with minimal disruption to the existing operation of the system. On-board battery back-up keeps the data in case of power failures. The ability to remotely interrogate the system is available within the EnviroMon accessories program by means of a dial up modem connection, if required. Most importantly the Enviromon system does not require a PC for continued operation.
Implementation of the EnviroMon System at Hillview
The picture on the left shows one of the earlier experiments using a cheap digital thermometer with extra sensor. No remote reading was possible with this approach. In another experiment the use of UHF radio transmitting temperature sensors was tried. A transmitter/sensor can be seen on the right in the picture. Although that approach looked initially promising, it was found that the transmitter range was far too short to be of practical use at Hillview Sanctuary.
The picture on the right shows a “patient” recovering from an operation. In the days before the EnviroMon system was in place there was no easy way to centrally and accurately monitor the temperature in the isolation enclosure. With the EnviroMon system a sensor is placed in an enclosure when needed. After use the sensor can be disinfected and stored, ready to be used again.
The ability of the EnviroMon system to run on simple four–core cable has proved to be a tremendous advantage to our set up. Long lengths of unwanted outdoor telephone trunk cable are often available and this cable being designed for outdoor use is ideal for the long runs, which we require. As stated in our requirements, the systems ability to keep it’s data and set points is crucial for us since power cuts in this rural part of Ireland are all too common.
Conclusion
The Pico EnviroMon system has now been use for many months. It is in 24/7/365 operation mode and has worked flawlessly. The ability to read the various temperatures from a central point, without having to go outside in all weathers and check the individual enclosures has been of tremendous benefit. Especially in the case of very young kittens and elderly sick cats the ability to closely monitor the temperature has been a real lifesaver for these animals.
Frequent use of disinfectant has not affected any of the components. The system has proven itself to be robust and reliable.
Hillview Animal Sanctuary wishes to express it deepest gratitude to Pico technology who were kind enough to donate the system that has been described here and is the subject of this application note.
