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Variable Speed Fire Pump Controllers were invented and released with a UL Listing for fire pump service in 2003 by Master Control Systems, Inc. [1] [2] Paragraph 10.5.5 in the 2003 edition of NFPA-20 recognized Variable Speed as an accepted method for operating the fire pump. Then in the NFPA-20 2007 edition, section 10.10 was added to clarify ...
Coded panels were the earliest type of central fire alarm control, and were made during the 1800s to the 1970s. A coded panel is similar in many ways to a modern conventional panel (described below), except each zone was connected to its own code wheel, which, depending on the way the panel was set up, would either do sets of four rounds of code until the initiating pull station was reset ...
There are certain exemptions like system maintenance and security lockdowns, where manual activation outside the control panel may be overridden. [1] Security alarms, emergency door releases, industrial fire suppression systems, and hazardous material leak alarms are all examples of specialty systems which are sometimes activated with similar ...
Jockey pumps are typically small multistage centrifugal pumps, and do not have to be listed or certified for fire system application. The control equipment for jockey pumps may however carry approvals. Jockey pumps should be sized for 3% of the flow of the main fire pump and to provide 10psi more pressure than the main fire pump (As per Code IS ...
Johnson and a group of Milwaukee investors led by William Plankinton incorporated the Johnson Electric Service Company in 1885 to manufacture, install and service automatic temperature regulation systems for buildings. [9] After Johnson died in 1911, the company decided to focus on its temperature control business for non-residential buildings.
For air-operated control valves, electrical signals from the control system are converted to an air pressure for the valve actuator in a current/pneumatic I/P converter. Upon loss of pneumatic or hydraulic pressure valves may fail to an open (FO) or fail to a closed (FC) position. Some instrumentation is self actuating.
DETROIT (Reuters) -U.S. automakers Ford Motor and General Motors will donate $1 million each, along with vehicles, to U.S. President-elect Donald Trump's January inauguration, company ...
A control loop is the fundamental building block of control systems in general and industrial control systems in particular. It consists of the process sensor, the controller function, and the final control element (FCE) which controls the process necessary to automatically adjust the value of a measured process variable (PV) to equal the value of a desired set-point (SP).