PROTECTION OF BUILDINGS AGAINST WATER OVERFLOWS BY MEANS OF ELECTRICITY.
This subject was forcibly brought to my notice some years ago by having been subjected to two rather uncomfortable and expensive overflows of water at my place of business.
We are protected against fire and theft, but there is no safeguard against water overflows, and the disquietude caused by this fact stimulated me in endeavoring to find means whereby I could protect myself, more especially as a loss of this nature would fall entirely upon me. The damage caused by water overflows is a very serious matter, particularly in large cities, frequently causing a loss of many thousand dollars, and involving business houses in expensive litigation.
I have, therefore, devised a system which provides an efficient and reliable safeguard against damage to merchandise and other property from overflows of water in buildings, generally resulting from theburstingof pipes, stoppage of drains or negligence, and sometimes from other causes.
The same consists of a method or system of automatically detecting an overtl >w or leakage of water in a building, which comprises means for directing such an overflow or leakage to an electric water-detecting device, which is normally inactive, but which becomes operative in the presence of water, to sound an alarm and shut off the water supply at the point of overflow or leakage, or to the building. The water-detecting device, which I call a hydrostat, can be inserted in the floor, basin, tub or tank, according to the kind of protection required.
Horizontal pipes are encased in a wooden box, made to slant slightly, so that a leakage cannot escape, but will be led to the hydrostat.
In protecting a floor, the plumbing is confined within an area limited in extent by a line of onehalf inch cleats nailed on the floor, from wall to wall, describing a circle or the shape required ; within this enclosure a series of conveying grooves leads to a strainer inserted in the floor and on which is fastened a hydrostat.
The electric devices, by means of which, in case of an overflow, the hydrostat is made to shut off the water supply and sound an alarm, consist of a battery, alarm bell and a trip apparatus. The first hydrostat I constructed consisted of two sets of conductors running at angles to each other and separated by a material which would act as an insulator when dry and become a conductor when wet. This was inserted in an aperture in the ceiling, directly under another aperture in the floor ; the latter was supplied with a strainer and was situated at the base of a series of converging grooves, so as to’catch any water which might overflow from the basin or other fixture. I found this apparatus entirely too sensitive, as a single drop of water was sufficient to shut off the entire water supply to the building, and furthermore the insulator became deliquescent from the moisture in the atmosphere, so I was compelled to abandon it.
* Read by Leopold Weil before the Franklin Institute, May 16, t888, and published in The journal of the Franklin Institute.
I have different forms of hydrostats for various purposes ; the one that I have here consists of a small vessel, provided with a suitable cap ; there are openings to permit the ingress of water and exit of air; I place in the vessel a float, which rises when water enters, until it comes into contact with the conductor and forces its free end, which is connected with one binding post, against, and into contact with, the other binding post in the cap, thus closing the circuit and operating the system.
The trip apparatus consists of an electro-magnet and an armature with a catch, which, in its normal position, engages with a lever. Upon this lever is suspended a weight, sufficiently heavy to operate the valve to which it is connected.
For the purpose of testing the system I place in the circuit a test button ; by pushing this button the water ought to be turned off, and in order to denote this I make a break in the bell circuit, which closes only after the valve has operated, thereby ringing this bell, which cannot ring unless the water has been actually shut off.
Now you have the system complete ; you will imagine this hydrostat inserted in a basin or bath-tub, as the case may be ; I will first push the button to see if everything is all right. Now I will proceed to pour water into this vessel, and when it reaches the proper height, you will see, it operates the valve and precludes the possibility of an overflow by shutting off the water supply.
We can protect a basin, bath-tub, tank, the pipes, the floor, or anything else, as may be needed. A basin or bath-tub provided with a hydrostat can be made proof against sewer gas by dispensing entirely with the overflow holes. This is of great importance in many modern houses, where the plumbing adjoins the sleeping apartments.
When employed :n hotels, the hydrostat is connected with the ordinary call-bell circuit, and in this way the office will immediately be notified, and the room in which the leakage would have occurred be located and overflow prevented. In business houses the greatest danger exists at the time when the occupants have left the premises. This could be guarded against by shutting off the water when locking up, and it ought to be done every night, because, unless there are people in the building, there is certainly no use for any water. It is, however, frequently neglected through carelessness or forgetfulness, and all of
the lawsuits which I have heard of in New York for damages from water overflows come under this category.
In order to provide an automatic method for turning off the water at night, I have provided a box into which must be placed the keys to the premises. I prefer to use the keys, because they must be used in locking up at the time when no water is wanted in the building. The operation is, viz.:
When the keys are removed from the lever it closes the main circuit and operates the valve.
The lever of the valve, when the water has been shut off, falls upon a spring which closes the alarm bell circuit; both circuits are now closed, the one having operated the valve to turn off the water and the other giving audible proof that this has been done. The bell continues to ring until the door to the box is closed. The valve cannot be kept open until the keys have been put back into the box, thus leaving the apparatus in condition to operate the valve to shut the supply pipe when the key is taken at night to close the building.
The apparatus can always be tested to ascertain if all the parts are in adjustment and good condition by opening the door of the box and removing the key. Thus in the morning when the box is opened to put the key in its place the alarm will be sounded if the apparattts is in working order.
In closing, I merely wish to add that a large insurance company is in operation in Frankfort, Germany’, with a capital of 1,000,000 marks, and their business is to insure against damages caused by overflows of water in buildings. With the system I have described no such precautionary measure is essential, but the very fact that in the old World water-damage insurance companies exist demonstrates the necessity for some kind of protection in this respect, and I hope the time is not far distant when the term “ modern improvements,” as applied to buildings, will include a system for the prevention of water overflows.