ZeroRPM Ambulance Idle Mitigation System | Idle Control System | REV Group

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the future with ZeroRPM™

An eco-friendly solution for your patients, your crew,
the environment, and your operational costs.


The ZeroRPM Idle Mitigation System

Your EMTs are never off-duty and neither is their ambulance. Always on call, your fleet is often idling all day and all night to keep vital equipment protected: HVAC, interior/exterior lighting, communications equipment, electrical systems; including batteries, chargers, narcotics, temperature-controlled compartments, life-support systems, and more. That’s why departments choose ZeroRPM, because when every second counts, an ambulance crew must always be ready to go.

With ZeroRPM, ambulance owners will see a decrease in fuel consumption, a reduction in CO2 emissions, and a decline in their vehicle operating costs. Designed to alleviate the expenses and complications that come from constantly running an ambulance’s engine, use of the ZeroRPM Idle Mitigation System (IMS) results in less risk to the environment and personal health. You’ll also see an extension of the ambulance’s chassis life, which means ZeroRPM is a win-win for patients, crews, and your entire ambulance fleet.

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What Is ZeroRPM?

ZeroRPM is a hands-free Idle Mitigation System (IMS) for your ambulance, enabling it to function the same when parked whether the engine is running or not. It is designed to virtually eliminate costly, and harmful, vehicle idling.

Automatically starting and stopping the engine to decrease fuel consumption, pollution, and maintenance costs, ZeroRPM allows complete use of the ambulance’s critical functions as if the engine were still on. While crews continue to have access to the vehicle’s A/C, heat, windows, lighting, accessories, vital equipment and more, ZeroRPM helps reduce the negative impact extended idling has on the environment, personal health, and vehicle operating costs.

ZeroRPM is a perfect idle-mitigation solution when your ambulance is on the scene of a call, parked at the emergency room, or in static standby for its next call.

How ZeroRPM Operates

Activating ZeroRPM couldn’t be simpler. When the vehicle is placed in park and the driver takes his or her foot off the brake, the ZeroRPM Intelligent Vehicle Management System takes full control of the engine’s operation, shutting down or re-starting the engine, as necessary, to provide seamless operation of all the ambulance’s systems with minimal, if any, engine idling.

When idle mitigation is activated, ZeroRPM continues to provide power to operate as if the engine is running, allowing idle-free use of radios, emergency lights, interior lights, oxygen and medical air, fresh air ventilation, chassis windows, etc.

ZeroRPM also continues to heat or cool the vehicle as requested, with the heat and A/C systems working as they normally would through the factory-installed vents and controls. For extreme cold weather climates, a fuel-fired heater can be added, providing enhanced idle-free heat.

While the engine is off, ZeroRPM will monitor multiple conditions and, if required, ZeroRPM will automatically restart the engine to ensure continuous use of the ambulance. The ZeroKey feature allows the crew to leave the ambulance unattended without the need to leave the key in the ignition.

ZeroRPM systems have an Intellimetrics option, allowing you to track vehicle usage and observe idle mitigation operation. This feature provides valuable data such as Vehicle Diagnostic Trouble Codes (DTC) to support vehicle maintenance, calculators to track fuel and maintenance savings, and tracking to identify other possible idle reduction areas.

There is even an additional temperature control on the ZeroRPM controller to enable the cab’s heat and air conditioning to be set to a specific temperature. When set, ZeroRPM will turn off the cab’s HVAC once the selected temperature is reached.

Available Options

ZeroRPM offers several configurations to meet your specific needs. The common configurations are listed, below. Please consult with your REV Ambulance dealer for more detailed information.

System Feature Summary Ims1 Ims1h Ims2h Ims3hac Ims4hac
PDMA Controller: Intelligent Vehicle Management System          
Intellimetrics Gateway Option: 3 Years of prepaid data. Access to online portal, offering dashboard tools and easy retrieval for offline data analysis.          
Maximum Continuous Runtime 30 Min 30 Min 1 Hour 1 Hour 2 Hour
Lithium Iron Power Module: None (Chassis Battery) None (Chassis Battery) 100 Amp Hour (1.25 KWH) 200 Amp Hour (2.50 KWH) 300 Amp Hour (3.75 KWH)
Heat (Chassis and Module): Provided through normal vents and controls Automatically Starts Engine to Provide Heat Chassis heat pump circulates existing engine heat Chassis heat pump circulates existing engine heat Chassis heat pump circulates existing engine heat Chassis heat pump circulates existing engine heat
Available fuel-fired auxiliary heat          
Air Conditioning (Chassis and Module): Provided through normal vents and controls Automatically Starts Engine to Provide A/C Automatically Starts Engine to Provide A/C Automatically Starts Engine to Provide A/C 6,000 BTU 12-volt Compressor 12,000 BTU 24-volt Compressor
ZeroRPM Air Conditioner
Power Module
IMS Controller

How It Pays Back

In addition to reducing the environmental impact of unnecessary idling, ZeroRPM dramatically reduces the cost of operations, providing real savings and payback on the investment.

While operating and idling conditions vary widely between agencies, the table indicates ranges of common costs associated with idling that ZeroRPM is designed to eliminate.

Costs lower estimate average estimate Higher estimate
Cost of Diesel Fuel Per Gallon $2.85 $3.18 $3.50
Gallons Used to Idle One Hour 0.50 0.75 1.00
Fuel Cost Per Idling Hour $1.43 $2.38 $3.50
Engine Hours Between Oil Changes 400 325 250
Cost Per Oil Change $100 $118 $135
Oil Change Cost Per Engine Hour $0.25 $0.36 $0.54
Total Cost Per Hour of Idling $1.68 $2.74 $4.04
Idle Hours Per 8 Hour "Shift" 1.50 2.50 3.50
Cost Per Shift $2.51 $6.86 $14.14
8 Hour Shifts Per Year 1,095 1,095 1,095
Idle Cost Per Year $2,751 $7,508 $15,483

Frequently Asked Questions

ZeroRPM is an award-winning company with award-winning Idle Mitigation Systems (IMS) and ClimateGuard (CG) systems. Founded in 2012, ZeroRPM has thousands of active systems in the field. IMS can be found in armored trucks, ambulances, fire engines, bucket trucks, work trucks, police vehicles and security vehicles.

An Idle Mitigation System (IMS) is how we describe the family of technology that allows us to transform a standard vehicle into a hybrid on the scene or job site. We use the acronym IMS as a nickname for the same system. You will see both Idle Mitigation System and IMS used universally in our marketing and technical documentation.

Through an Intelligent Vehicle Management System that allows you to use all of the chassis features without idling an engine to do so. Simply put, the IMS does the same job, when the engine is off, that belt-driven alternators and air conditioning compressors do when the engine is on. The patented IMS HVAC functionality is seamlessly integrated to provide air conditioning and heat through the factory vents.

The IMS is tightly integrated with the vehicle chassis. So much so that the operator will only experience two differences in operation protocol. The first change is that the engine will automatically shut down when placed into park. The second change is that the IMS will automatically start the engine when the operator places their foot on the brake pedal prior to shifting the transmission into drive.

The nature of how ambulances are used dictates that the vehicle is stationary for a large percentage of their life. Much of this time is away from shore-power, and the engine must idle to supply power and HVAC to the ambulance. A properly configured IMS can eliminate all of the engine idling for power supply and HVAC.

Once the vehicle is in park, for an automatic transmission, or in neutral with park brake for a manual transmission, and the IMS controller determines that the engine is being allowed to idle.

No. The IMS controller only allows the system to manage the engine stop or start when the vehicle is in a condition for prolonged stationary use. The system automatically stops the engine when the vehicle is in park, for an automatic transmission, or in neutral with park brake, for a manual transmission.

ZeroRPM assembles ultra-safe battery packs, in Bremen, Alabama. The IMS battery system includes integrated electronics that monitor and protect every cell. The battery base cells chemistry is LiFeMnPO4; they are inherently safer since they do not create oxygen in extreme heat situations.

This is dependent upon multiple variables including total amperage load of the ambulance, HVAC requirements, IMS configuration, and system program settings. A typical application will be designed to provide a minimum of one (1) hour of continuous operation in IMS mode during worst-case circumstances. Many situations will allow up to four hours of continuous runtime.

Virtually every chassis and ambulance module feature will operate as if the engine is on. The IMS software can be programmed to automatically start when a feature is requested that requires the engine to be on, such as emergency lights, PTO or a winch.

The engine will automatically start when the operator presses the brake pedal. The standard chassis ignition process will also work when in IMS mode.

The IMS family of technology is designed to integrate with your vehicle with minimal intrusion. Elements of the system can be installed in various locations throughout the vehicle. The systems are easily configured for different vehicle types. Contact your representative for REV Ambulances to learn how we will configure your IMS.

All REV Ambulance brands are available with the IMS integrated from the factory. While the factory integration is the most efficient, an IMS is a retrofit friendly solution for any vehicle in your fleet. Contact your representative for REV Ambulances to learn about the best IMS configuration for your retrofit application.

The REV dealer network will provide service and support. REV will provide maintenance and repair training programs for large fleets that require independence.

ZeroRPM warrants all system elements against failure due to defects in materials and workmanship for one (1) year. Extended battery warranties are optional at an additional cost.

An IMS does not void the factory warranty. Adding an IMS to your vehicle can reduce OEM warranty claims by mitigating engine idle time and thus engine hours.

The typical payback for a properly sized IMS is between two and three years. IMS systems are available for basic idle mitigation, without battery powered air conditioning, on the lower cost end of the spectrum. Advanced systems are available with extended runtime, high output battery powered air conditioning and additional functionality. Please contact REV to specify and price your desired configuration.

ZeroRPM’s Intellimetrics tool continuously records and summarizes vehicle performance data into useful information to understand and optimize the savings associated with idle mitigation and operator behavior at the job site. The information is available on the integrated user interface screen that comes with the idle mitigation system. The information can be transmitted wirelessly by adding the optional Intellimetrics Gateway. Gateways can be shared across a fleet or dedicated to each individual vehicle for hassle-free information collection to the Intellimetrics portal for graphical analysis and data export.

ZeroRPM’s Intellimetrics does not use GPS to track the vehicle's location. Only engine and idle mitigation related data are stored and transmitted to the Intellimetrics portal. Each device is listed on the monitoring site only as an alphanumeric code assigned to the monitoring device itself. Organization and vehicle data are not recorded or posted on the site other than the last 8 digits of the VIN. The only information that is used by ZeroRPM and its representatives includes the dates, idle times, and drive times for the device. Only ZeroRPM management and the representative working with the department have access to this information. The cellular provider has no access to the data being collected.

Proper launch training programs combined with Intellimetrics analysis of performance ensures optimal results. ZeroRPM provides detailed user manuals and quick start training guides to simplify the rollout of IMS equipped vehicles in the fleet.

IMS systems have been installed in over 25 distinct vehicle chassis types from 2010 through the current model year. IMS models are available in a wide range of cost and options to meet your payback expectations. Contact where you buy your ambulances to learn more about which ZeroRPM Idle Mitigation System is right for you and your vehicle type.

Yes. The IMS is an auxiliary system that does not impede the vehicle’s functionality. If the IMS stops working the vehicle (including all electronic and HVAC components) will run as though the IMS were not present.

Yes. Each individual customer has secure access to the Intellimetrics portal to view and analyze their information.

Vehicle start time is not affected by our system. The vehicle will start at the same speed it would without the IMS installed.

The IMS is tightly integrated to the chassis. The IMS automatically engages idle mitigation operation when the vehicle stops and is placed in park. The IMS automatically disengages when the vehicle is started, by pressing the brake pedal or turning the ignition switch and placed into drive. The operator is not required to do anything different to operate a vehicle with an IMS than he or she would otherwise.

The system does not interfere with the radios, lights, computers, or other equipment on the vehicle. The safe lithium-ion battery system operates in the same voltage ranges as lead-acid batteries and stock alternators. One of the key features of the system is that it provides and monitors power for all electrical needs of the vehicle and onboard equipment.

The IMS only uses the lead acid batteries for engine starting. The lead acid battery voltage will be maintained at an optimal high voltage level since they are immediately recharged after a start cycle and not used for deep cycle energy. Starter failures are driven by start cycles with low voltage levels. Since the IMS maintains a high lead acid voltage level, the additional start cycles associated with the engine off idle mitigation do not cause premature failures. ZeroRPM has systems in the field with over five years of operation without any known IMS related starter failures.

Learn More About ZeroRPM

Already know the ZeroRPM system is right for your fleet? Looking to find out more about how this hands-free system works? No matter your request, simply fill out the form below and a member of our team will be in contact with you in no time.

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