Liebert® EXM™ UPS
Single-Module Uninterruptible Power System
These specifications describe requirements for an Uninterruptible Power System (UPS) optimized for maximum efficiency. The UPS shall automatically maintain AC power to the critical load within specified tolerances and without interruption during failure or deterioration of the normal power source.
The manufacturer shall design and furnish all materials and equipment to be fully compatible with electrical, environmental and space conditions at the site. The UPS shall include all equipment to properly interface the AC power source to the intended load and shall be designed for unattended operation.
The UPS and all associated equipment and components shall be manufactured in accordance with the following applicable standards:
The UPS shall be UL listed per UL Standard 1778, Fourth edition, Uninterruptible Power Supplies, and shall be CSA Certified.
The UPS shall be provided with a Short Circuit Withstand Rating (SCWR) label denoting the maximum source fault short circuit current that is applicable to the unit. The withstand rating shall be independently verified by a nationally recognized, third-party lab.
The UPS shall withstand input surges to both the rectifier and bypass when configured as either a single-input or as a dual-input unit without damage as per the criteria in EN62040-2 (4kV). The manufacturer shall provide evidence of compliance upon request.
The UPS shall comply with FCC Rules and Regulations, Part 15, Subclass B, Class A. This compliance is legally required to prevent interference with adjacent equipment. The UPS shall have a label stating FCC compliance. The manufacturer shall provide evidence and test data of compliance upon request.
The UPS shall be compatible with the wiring practices, materials and coding in accordance with the requirements of the National Electrical Code, OSHA and applicable local codes and standards. Provisions shall be made in the cabinets to permit installation of input, output and external control cabling using raceway or conduit for top and bottom access to input, output, bypass and DC connections. Connection cabinets shall provide for wiring gutter and wire bend radius as defined by the NEC and UL.
The UPS shall be sized to provide a minimum of ____kW output (unity load power factor rating)
The UPS output capacity shall have the option to enable scalability at the time of ordering and shall be upgradeable by Vertiv Services.
Models shall be available in two frames:
200kVA frame – Scalable from 50kVA to 200kVA (50kVA hardware increments)
250kVA frame – Scalable from 50kVA to 250kVA (50kVA hardware increments).
The UPS shall be able to supply all required power to full rated output kVA loads with power factor from 0.5 lagging to 0.9 leading. The UPS shall also work from unity power factor to 0.5 leading power factors subject to derating.
Load voltage and bypass line voltage shall be 480VAC, three-phase, three-wire plus ground. Input voltage shall be 480VAC, three-phase, three-wire plus ground. The AC input source and bypass input source shall each be a solidly grounded wye service.
The battery shall support the UPS at 100% rated kW load for at least _____ minutes at 77°F (25°C) at startup.
The UPS shall have an active power factor-corrected IGBT converter/rectifier, capable of maintaining input power factor and input current total harmonic distortion (THDi) within specifications without an additional input filter.
The UPS shall be of transformer-free design, requiring no internal transformer in the main power path for the basic operation of the module. Optional transformers in cabinets or otherwise external to the basic UPS module shall be permissible to provide isolation and/or voltage transformation.
Modes of Operation
The UPS shall operate as an on-line reverse transfer system in the following modes:
Normal: The critical AC load shall be continuously powered by the UPS inverter. The rectifier/charger shall derive power from the utility AC source and supply DC power to the DC-DC converter, which in turn shall supply the inverter while simultaneously float charging the battery.
ECO Mode: The critical AC load shall be continuously powered by the bypass with the inverter available to power the load if the bypass source voltage or frequency exceeds adjustable parameters of power quality.
Battery: Upon failure of utility AC power, the critical load shall be powered by the inverter, which, without any switching, shall obtain its power from the battery plant via the DC-DC converter. There shall be no interruption in power to the critical load upon failure or restoration of the utility AC source.
Recharge: Upon restoration of the utility AC source, the rectifier shall supply power to the output inverter and to the DC-DC converter, which shall simultaneously recharge the batteries. This shall be an automatic function and shall cause no interruption to the critical load.
Bypass: If the UPS must be taken out of service, the static transfer switch shall transfer the load to the bypass source. The transfer process shall cause no interruption in power to the critical load. An optional external wrap-around maintenance bypass shall be used to ensure full isolation of the unit for the service of internal components while providing safety from arc flash and in compliance with OSHA requirements.
Off-Battery: If the battery only is taken out of service, it shall be disconnected from the DC-DC converter by means of an external disconnect circuit breaker (in the case of external batteries). The UPS shall continue to function and meet all of the specified steady-state performance criteria, except for the power outage backup time capability. If multiple battery strings are used, each string shall be capable of being electrically isolated for safety during maintenance.
The solid-state power components, magnetics, electronic devices and overcurrent protection devices shall operate within the manufacturer’s recommended temperature when the UPS is operating at 100% critical load and maintain battery charging under either of the following conditions:
Any altitude within the specified operating range up to 3300 ft. (1000m) elevation
Any ambient temperature within the specified operating range of 32°F to 104°F (0°C to 40°C)
Voltage: Input/output voltage specifications of the UPS shall be
Rectifier AC Input: 480V, three-phase, three -wire-plus-ground
Bypass AC Input: 480V, three-phase, three -wire-plus-ground
AC Output: 480V, three-phase, three -wire-plus-ground
Voltage Range: +20%, -15% at full load; -40% at half load
Frequency Range: 40 - 70Hz
Maximum Inrush Current: UPS inrush current not to exceed 1.5 times rated input current
Input Current Walk-In: The UPS shall contain a controlled module walk-in to minimize inrush current upon auto-restart. The module walk-in is programmable for a 1 to 5 second delay.
Power Factor: Minimum 0.99 at full load with nominal input voltage
Current Distortion: Less than 3% THD at full load linear input current and less than 5% at full load non-linear input current in double-conversion mode
Surge Protection: Withstands input surges of 4kV (Line to ground) without damage as per criteria listed in EN 61000-4-5: 1995
Short Circuit Current Rating: Units shall carry as standard 65kA Short Circuit Withstand Rating. All ratings shall be certified and a label shall be applied to the unit clearly identifying this rating as required by the National Electrical Code.
Load Rating: 100% of load rating at 104°F (40°C) for any load from 0.5 lagging to 0.9 leading
±1% RMS average for a balanced, three-phase load
±2% for 100% unbalanced load for line-to-line imbalances
Voltage Adjustment Range: ±5% for line drop compensation adjustable by factory service personnel
Synchronized to bypass: ±2.0Hz default setting, (adjustable by factory service personnel)
Balanced loads 120° ±0.5°
100% unbalanced loads 120° ±1.5°
Voltage Transients (average of all three phases):
Response: Meets ITIC and CBEMA Curve Requirements
Complies with IEC/EN 62040-3: 2010 Figure 2 Curve 1, Class 1
Transient Voltage Deviation, RMS: 5%
Recovers within 60ms
Overload at Full Output Voltage with ±1% voltage regulation:
105% - 110% of full load for 60 minutes at 104°F (40°C) ambient
110% - 125% of full load for 10 minutes at 104°F (40°C) ambient
125% - 150% of full load for 60 seconds at 104°F (40°C) ambient
>150% of full load for a minimum of 200 milliseconds at 104°F (40°C) ambient
The UPS chassis shall have an equipment ground terminal.