Tripp Lite's EMS1250UL inverter with integrated charging system provides automatic, uninterruptible DC-to-AC power for critical on-board equipment. Ideal for installation by ambulance/EMS vehicle manufacturers, dealer or EMS service for OEM, replacements and upgrades. Supplies up to 1250 watts of continuous 120V AC power to 2 AC outlets from any 12V battery or automotive DC source. When AC cable is connected to a shore power source, commercial power passes through to connected equipment and the battery set is recharged via 3 stage, 14/55 amp selectable charging system. This unit can also function as a UPS system, responding to blackouts and voltage fluctuations with a near instantaneous automatic transfer to battery-derived AC output. Convenient Anderson DC input quick connector on the unit with extra Anderson DC input connector included in the box (user supplies batteries and cabling). Reliable large transformer design with efficient PWM sine wave output and frequency control powers resistive electronic loads or large inductive motors, compressors and other items with high current needs on startup. Included APSRM4 wired remote power switch with full status LEDs provides remote power inverter on/off switching and continuous status information (APSRM4 included). Supports an unlimited amount of runtime with any number of user-supplied batteries connected. Highly adaptable to a variety of applications and site conditions with adjustable charger settings for wet/gel battery types and selectable line to battery power transfer voltages. Includes AC input surge suppression. Includes hospital grade plug and outlets with GFI (ground fault interrupter) protection. TUV tested to UL458 (mobile inverter) and CAN/CSA-C22.2 No. 107.1-01. Meets GSA ambulance specification KKK-A-1822.

NOTE: To protect against high current draw that may occur during inverter failure, a fuse link rated at 200a should be positioned no more than 18" from the EMS1250UL's battery in the positive line.


- EMS1250UL serves as an automotive or stationary DC-to-AC inverter with automatic line-to-battery transfer and integrated battery charger
- Supports 120V AC output from a 120V AC line power source or 12V DC battery source
- 16.6 millisecond automatic transfer between line and battery power supports UPS protection during blackouts and voltage fluctuations for equipment compatible with a one cycle transfer time
- 1250 watts continuous AC output in inverter mode, 1440 watts continuous AC output in AC mode
- Double Boost™ inverter output supports momentary startup loads up to 200% of the continuous rating for up to 10 seconds
- OverPower™ inverter output supports longer duration overloads to 150% for 1-60 minutes under ideal battery and temperature conditions. (For best results, utilize OverPower usage for as short of a duration as possible, ensure battery bank and cabling is able to provide full nominal DC voltage under load and allow inverter/charger to fully cool before and after OverPower usage.)
- 3 stage, selectable 14/55 amp battery charger with adjustable settings for wet/gel battery types offers fast, reliable battery recharging
- Anderson quick connect DC wiring terminals safely accept input from attached battery bank
- Protected hardwire output passes 120V line power or inverter output through to connected equipment
- Reliability enhanced large-transformer design tested to UL (USA) and CSA (Canada) standards
- Moisture-resistant construction enables vehicular or marine operation in high humidity environments
- 3 position operating mode switch supports "AUTO" mode to enable automatic transfer between DC and AC modes, CHARGE-ONLY to maintain a full battery charge when AC is present without auto transfer and SYSTEM OFF settings
- Set of six front panel LEDs display AC/DC operational modes, overload status, DC voltage level, shutdown status and system fault status
- Set of 4 configuration dipswitches support wet/gel battery charging profiles, adjustable 135/145V high voltage auto transfer during overvoltages and selectable 75/85/95/105V AC low voltage auto transfer during brownouts
- Set of 4 additional configuration dipswitches support 4 levels of charger limiting relative to output load size, a battery equalization program and battery charger low/high/off settings
- Resettable 12A charger AC input breaker and resettable 12A AC output breaker and automatic 2 speed cooling fan protect the inverter from load and temperature related failures
- Grounding lug properly connects the inverter/charger system to earth ground or vehicle grounding system
- Automatic overload and thermal shutoff safely turns off inverter as excessive loads or overheating conditions develop
- Front panel remote control connector enables remote off/on switching (APSRM4 remote control switch with status LED display and 50 ft cable included). APSRM4 accessory also includes user configurable jacks to support inverter shutoff or startup as a vehicle ignition is engaged
- Load sensing control dial enables adjustable load threshold required to automatically turn the inverter on and off in DC mode as load conditions change

Package Includes
- EMS1250UL Inverter/Charger
- Instruction manual with warranty information
- Wired Remote Switch with full LED status indicators (model APSRM4)
- 2 Anderson DC connectors (1 on the unit and 1 included in the box)
- RoHS compliant