Fire Pump Engines Overview

Diesel Fire Pump Engines

- for -

F.M. Approvals- by -

James S. Nasby

Columbia Engineering

C.E. F.M. Approvals 2

Topics to be Covered Constant (Variable) Speed Engines PLD Variable Speed Engines Electronic ECM (ECU) Engines Electrical Components Operating Environment Design Parameters Testing & Evaluation Installation Considerations


Constant (Variable) Speed Engines

Caterpillar Clarke Cummins Also U.L. Listed: Deutz Edwards

Although designed to run at a Fixed Speed, NFPA-20 considers all engines to be variable speed devices by nature of the speed governor and also for overspeed (overpressure) considerations.

Note: Propane engines have been proposed for NFPA-20 2010 Edition.


15201 Cummins NT & VT Series, Historic


15030 Caterpillar External Diagram


15034 Cummins ECM Engine


PLD Variable Speed Engines

Clarke PLD Pressure Limiting Driver.This is a hydraulic closed loop (feedback)

system which compares the pump output pressure to a spring force by was of a hdraulic cylinder. The cylinder operates to vary the speed governor set point. This mechanical system will become obsolete when mechanical governors become obsolete.


Clarke PLD Engine


Electrical Components Batteries Gages Contactors (Two) Valves – Not all are Manual Operable

Single Coil Dual Coil (Energized During Cranking)

Speed Control Governor (Mechanical) Electronic – ECM (ECU) Not all have means for simulating

an Overspeed Condition

Speed Switch – Critical Item Starter Motor (One or Two)*

Note: The dual starter motor Clarke engine does not manually operable contactors.


Electronic ECM (ECU) Engines

Cummins (U.L. & F.M.) Clarke (U.L. & F.M.) (High current draw in the Alternate ECM position)

Notes:1) Some designs keep the ECM powered up

continuously, others only when needed.2) Changing to single ECM design was proposed

to NFPA-20 and passed. However, this was changed in the ROC meeting to keeping Dual ECMs and adding requirement for Automatic Switchover with Manual Over-ride Switch.


Electronic Control ModulesSome ECUs won’t initialize if Crank Signal (Terminals 9 or 10) Precedes the Fuel Signal (Terminal 1)Replacement ECUs for Fire Pumps are Non-Standard. They have to be programmed by the dealer before they can be used.Some are Always Energized, others Boot Up at Run Time.Some Alternate ECM Draws Significant Current in the Alternate ECM Mode (Due to Relay Currents)ECMs May Not Operate at Voltages Below 10.0 Vdc (Single Battery Cranking)


Upcoming Change to ECM’s ??(Not Balloted A/O 2008.10.21)

_______________________________________________________________________________________________20-?? Log #29(11.2.4.3.2)_______________________________________________________________________________________________Comment on Proposal: 20-106Reccomendation: Add additional text, such as:11.2.4.3.4 When used on electronic engines (ECM/ECU equipped engines), the speed switch shall include

provisionsfor testing it's overspeed circuitry.Exception: Engines equipped with other means for testing overspeed shutdown operation with either EMC/ECU._______________________________________________________________________________________________20-?? Log #30(11.2.4.12)_______________________________________________________________________________________________Comment on Proposal: 20-107Reccomendation: I disagree with Committee Action accepting the Proposal to eliminate the redundant

ECM/ECUmodule on electronic engines. E.g.: Reject the proposal._______________________________________________________________________________________________20-?? Log #79Comment on Proposal: 20-107[Summary: Keep dual ECM’s and change manual change manual switch to automatic and add a manual over-

ride switch.]_______________________________________________________________________________________________


Starting Contactor

Manually Operable Versions are, or should be, U.L. Listed under U.L. Standard UL-218A


U.L. Listees for Contactos


Diesel Driver & Fuel Switch & Engine Gage Panel

Caterpillar Fire Pump Engine

MCS 4817 Low Fuel Switch

Typical Engine Gage Panel


18105 Clarke Dual Fuel Coils


15042 Clarke Dual Starter


Operating Environment

Environmental Conditions: Indoor, Outdoor, Temperature (High & Low) Cooling Heating Combustion Air Horsepower Derated for: Altitude Higher Ambinet Temperature


Dual Battery Operation

Diesel Battery Requirements

- Two banks of batteries are required.- Each must have capacity to crank the engine for 180 Seconds (Twelve 15 Sec. Cranks).

-Typically: - the batteries are SAE 4D or 8D types; - Two 12 Vdc Batteries on 12 Volt Engines - Four 12 Vdc Batteries on 24 Volt Engines - Eight 12 Vdc Batteries on Large Engines*

12 V

24 V

* Requires 20 Amp chargers to meet the 24 Hour Re-Charge time requirement.


Engine Drive

CombustionAir

-and-

RoomCooling

Most EnginesWater Cooled


Alternate Method for Combustion Air

_______________________________________________________________20-147 Log #46 Final Action: Accept in Principle(A.11.3.2.3)_______________________________________________________________Submitter: James S. Nasby, Skokie, ILRecommendation: Add new paragraph at end of A.11.3.2.3 to read:Another method of supplying combustion air is to a vent pipe, with rain cap, extending

thru the roof, or outside wall, of a pump house which extends to within six inches of the floor of the pump house. This passive method prevents heat loss in the winter. Successful installations use a 4”, 67” or 8” vent pipe depending on the size and number of engines involved.

Substantiation: Suggest method has long been used; but, is little known. It avoids the inherent problems with A.C or D.C. power operated louvers. It also results in very little pressure drop. In frigid weather, only the floor directly under the vent pipe becomes a little cold.

Committee Meeting Action: Accept in PrincipleRevise proposed language to read: A.11.3.2.3 Another method of designing the air

supply ventilator in lieu of dampers is to use a vent duct, with rain cap, extending thru the roof, or outside wall, of a pump house which extends to approximately six inches of the floor of the pump house. This passive method reduces heat loss in the winter. Sizing of this duct must meet the requirements of 11.3.2.1.

Committee Statement: Meets the intent of the submitter.

Note: this method can sometimes eliminate louvers altogether.


Design ParametersBattery Voltage Variation

The Engine and Controller must function reliably over a 250% voltage range.

Battery Banks Sized for 12 @ 15 Sec Cranks (180 Seconds per bank)

FM-1321/23 Hold-up Time Requirement (Note NFPA Proposal 21-112 and Comment #100)

Currents: Engine Wiring (Cabling) and Components Must Accommodate:

Cranking Currents (500 Adc or more) Breakaway Currents (1,200 Adc or more) Contiuous Charging Current with a typical RMS ratio of

1.8 times the rated D.C. Current.*

* E.G.: 18 Arms current flow for a 10 amp charger due to ripple current.


Design Parameters

Battery Sizing Battery Banks Sized for 12 @ 15 Sec Cranks (180

Seconds per Bank) This is to allow one Automatic Six Crank Cycle plus Six more Manual Cranks with one inoperative or missing battery.

FM-1321/23 Hold-up Time Requirement 48 Hours -or- 72 Hours -or- 90 Hours -or- 96 Hours ??

Note NFPA Proposal 21-112 and Comment #100 stands at 72 Hours, but not Balloted yet.


Testing & Evaluation

F.M. Standard FM-1333 Low Temperature Testing With or Without Heaters

U.L. Standard UL-1247 Low Temperature Testing With or Without Heaters

Voltage Margin Testing (Future?)


Engine Installation Considerations

Environmental Sprinklered Pump Room Outdoor Hazardous Locations, Explosion Proof:

Motor, Controller, Wiring

Air Filter Protection from Getting Wet Other

Salt Air Wind Blown Sand or Dust Temperatures Altitude


Questions ?

Fire Pump Engines Overview

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