насос сплинкерной системы пожаротушения

Принцип работы насосной установки спринклерной системы пожаротушения,  в  состав которой входит жокей-насос
В случае падения давления воды в спринклерной системе, первым включается жокей-насос. Если расход воды небольшой и жокей-насос справляется с восполнением утечки, то через некоторое время после достижения верхнего предела заданного давления он выключится. Если же это не протечка, а открылось несколько спринклеров и расход воды значительный, то даже при работающем жокей-насосе давление продолжает падать. В этом случае, по сигналу второго реле давления, включается пожарный насос. Резервный агрегат включается в случае невыхода основного на рабочий режим. Независимо от того, потушен пожар или нет, пожарные насосы сами не отключаются, их можно выключить только вручную со шкафа управления.
[http://www.airweek.ru/pr_news_137.html]

Jockey Pump

A jockey pump is a small pump connected to a fire sprinkler system and is intended to maintain pressure in a fire protection piping system to an artificially high level so that the operation of a single fire sprinkler will cause an appreciable pressure drop which will be easily sensed by the fire pump automatic controller, causing the fire pump to start. The jockey pump is essentially a portion of the fire pump's control system.
In the U.S.
The application of a jockey pump in a fire protection system is covered by documents produced by the NFPA (National Fire Protection Association, ) known as NFPA 20 "Fire Pumps" Standard and NFPA 13 "Design and Installation of Fire Sprinkler Systems". These must be inspected as with any other part of the system per NFPA 25 "Inspection and Testing of Water-Based Fire Protection Systems".Fire protection systems are governed in most states by statute, building code, and/or fire code.
In India
This jockey pump is also a must while designing the Fire Hydrants Pumps skid for Industrial installations.While the logic followed for the effective operation of the fire fighting pumps may depend upon or vary as per the regulations in a particular country, in India, the pump manufacturers like Mather-Platt with standard Fire Pumps generally adhere to the TAC guidelines (Tariff Advisory Committee guidelines).
Although India's premier manufacturer Kirloskar Brothers Limited, with approvals from UL and FM Global, LPCB, ASIB: follows TAC guidelines (Tariff Advisory Committee guidelines), or FM GLobal and UL standards depending on the clients needs.
If one is following the TAC guidelines, follow this approach

*Once the complete fire fighting circuit is under pressure by operating the pumps for sufficient time provided all the fire hydrant valves (Single yard hydrants, Fire escape hydrants, etc)are closed, the main pump stops.
*Due to some leakages somewhere in the fire fighting piping circuit, when there is a loss of system pressure which will be constantly monitored by the Pressure sensors in the circuit, the jockey pumps receives a signal to start from the automatic control panel, and will run to augment this loss of pressure by pumping more water into the circuit. Once the pressure is maintained as per the set point, it stops.
*If any hydrant valve is opened due to some fire and water is consumed, then the jockey pump due to its small capacity compared to the main pumps (one running, one stand-by)in terms of volumetric capacity, the main pump will start and then the jockey immediately stops.This way jockey pump is important which senses the loss of pressure in the circuit first.

[http://en.wikipedia.org/wiki/Jockey_pump#Jockey_Pump]