UPS Battery BackupsStandby (Offline)

EXR Series 90000966 UPS Battery Backup Manual

Setup, everyday use, maintenance and troubleshooting for the 1,000 VA / 900 W rack-mount standby UPS, with verified specifications.

  • Rating1,000 VA / 900 W
  • TopologyStandby (Offline)
  • Efficiency98.5%
  • Runtime at half load17 min

About the EXR Series 90000966

The EXR Series 90000966 is a 1,000 VA / 900 W rack-mount standby UPS certified under the ENERGY STAR program for uninterruptible power supplies. It is marketed as the EXR1000RT2U.

It can support up to 900 W of connected equipment (1,000 VA apparent power, a 0.90 output power factor). It is rated for 78–164 V, 44–66 Hz input and 97–141 V output. It has 8 outlets, all with battery backup and surge protection.

ENERGY STAR weighted efficiency is 98.5%, and 98.3% at half load. With nothing connected it draws 6.35 W. Its weighted efficiency is higher than 45% of the 95 Standby (Offline) models in our database.

The manufacturer lists it for consumer and commercial applications.

Specifications

EXR Series 90000966 specifications
BrandEXR Series
Model number90000966
Model name / seriesEXR1000RT2U
TopologyStandby (Offline)
Apparent power rating1,000 VA
Real power rating900 W
Output power factor (W/VA)0.90
Default normal modeVFD (voltage and frequency dependent)
Intended applicationsConsumer, Commercial
Rated input voltage78–164 V
Rated output voltage97–141 V
Input frequency44–66 Hz
Total outlets8
Battery backup + surge outlets8
Battery locationInternal
Runtime at full load5 min
Runtime at half load17 min
Battery warranty3 years
Weighted efficiency (ENERGY STAR)98.5%
Efficiency at 25% load96.9%
Efficiency at 50% load98.3%
Efficiency at 75% load98.5%
Efficiency at 100% load98.5%
Input power at no load6.4 W
Rack-mountableYes
Rack height2 U
Height3.5 in.
Width21.9 in.
Depth19.0 in.
Modular designYes
Communication portsserial (RS-232), USB, Ethernet
Management protocolsHTTP, SNMP
Manufacturer take-back programYes

Safety information

  • Plug the UPS directly into a properly grounded wall outlet. Do not plug it into a surge protector, power strip or extension cord, and do not plug a power strip or surge protector into its battery outlets unless the manufacturer explicitly allows it.
  • Do not connect laser printers, space heaters, hair dryers, vacuum cleaners or other high-current appliances to the battery outlets; their surge current can overload the UPS.
  • The UPS contains a battery that can deliver dangerous energy even when the unit is unplugged, and its outlets may be live on battery power. Do not open the enclosure except to replace batteries as described in the manual.
  • Install the UPS indoors in a clean, dry, well-ventilated location away from heat sources and direct sunlight. High temperatures shorten battery life sharply.
  • Battery-equipped UPS units are heavy. Use at least two people (or a lift) to move or rack-mount the unit, and install it in the lowest available rack position to keep the rack stable.

Installation and first-time setup

Size the load first. Add up the wattage of the equipment you plan to protect (check each power supply label or measure it with a plug-in meter). Keep the total below the 900 W rating — ideally under about 720 W (80%) to leave headroom for start-up surges and battery aging. The 1,000 VA figure is apparent power; the watt rating is the one that limits most modern IT equipment.

  1. Inspect and position

    Unpack the UPS and check for shipping damage. For rack installation, mount the rails (it occupies 2U) and slide the UPS in with a helper; tower units stand upright on a hard floor.

  2. Connect the battery

    Many UPS units ship with the battery disconnected for safety. If so, connect it as shown in the quick-start guide before plugging in.

  3. Connect input power

    Plug the UPS into a grounded wall outlet on a circuit that is not heavily loaded by other equipment.

  4. Charge the battery

    Turn the UPS on and let it charge for several hours before relying on full runtime. Equipment can be connected and used during charging, but runtime will be limited until the battery is full.

  5. Connect equipment

    Plug computers, network equipment and storage into the 8 battery-backup outlets.

  6. Set up automatic shutdown

    Connect the USB cable from the UPS to the computer and install the manufacturer's power-management software (or use the operating system's built-in UPS support) so it shuts down gracefully before the battery runs out. Connect the Ethernet management port and configure its IP address so servers and administrators can monitor the UPS over HTTP and SNMP.

  7. Run a self-test

    Once the battery is charged, start a self-test (usually by holding the power or test button, or from the software) to confirm that the UPS transfers to battery correctly.

Using your UPS

How this UPS protects your equipment

As a standby (offline) UPS, it passes utility power through to your equipment, with surge protection, and switches to battery within a few milliseconds when the power fails or voltage moves outside its limits. It is best suited to desktop computers and home networking gear. Its default operating mode is classified as VFD (voltage and frequency dependent).

Battery runtime

According to the certification record, the internal battery provides about 5 minutes at full rated load (900 W) and about 17 minutes at half load (450 W). Runtime is not linear — halving the load usually more than doubles it — and it falls as the battery ages or gets warm. Use the runtime to ride through short outages and to shut systems down cleanly during longer ones.

Monitoring and alerts

The UPS provides serial (RS-232), USB, and Ethernet communication. Supported management protocols include HTTP and SNMP, so it can integrate with network-management systems. Configure email or SNMP alerts for on-battery, low-battery, overload and replace-battery events.

Alarms and everyday use

  • An intermittent beep usually means the UPS is running on battery. Save your work; if the outage continues, shut down connected equipment before the low-battery alarm.
  • A continuous tone or overload indicator means the connected load is too high. Unplug non-essential devices from the battery outlets.
  • Leave the UPS switched on and plugged in at all times so the battery stays charged.
  • If the UPS switches to battery frequently on a generator or in an area with unstable voltage, adjust its input sensitivity setting as described in the manual.

Care and maintenance

WhenWhat to do
MonthlyCheck the front-panel status or software for alarms, confirm the load percentage, and make sure vents are clear of dust and obstructions.
Every 6 monthsRun a self-test (or confirm the automatic self-test passed). Where supported, perform a runtime calibration during a maintenance window, as it discharges the battery.
At the interval in the manualReplace the energy-storage components when the UPS reports end of life or fails a runtime test.
AnnuallyCheck for firmware and software updates and confirm that automatic shutdown still works by running a controlled test.
At end of lifeReturn used batteries or the complete unit through the manufacturer's take-back program or a certified battery recycler.

Troubleshooting

Use the front-panel indicators, display messages and event log to narrow down problems. For specific alarm codes, consult the manufacturer's manual or support line.

ProblemPossible causeWhat to try
UPS will not turn onBattery disconnected or deeply discharged; input breaker or fuse open; no utility power.Check the battery connection, verify the outlet or input breaker, and let the UPS charge for several hours before trying again.
Beeps and runs on battery with power presentInput voltage or frequency outside limits; loose input plug; generator power.Check the input connection, try a different circuit, and adjust input sensitivity if the manual permits.
Overload alarmConnected load above the rating; high inrush device on battery outlets.Reduce the load below 900 W and move printers or heaters off the UPS.
Short runtime or self-test failureAged or hot battery; battery not fully charged.Charge fully and retest; replace the battery if runtime remains well below the rated figures.
Replace-battery indicator onBattery at end of life.Order the specified replacement battery and replace it as described in the manual (or by service for larger units).
Site wiring fault indicatorMissing ground or reversed hot/neutral in the building wiring.Have a qualified electrician inspect the outlet and wiring before connecting equipment.
Computer does not shut down automaticallyCommunication cable not connected; software not installed or not configured.Connect the USB or serial cable (or configure the network card), install the management software, and test with a simulated outage.

Energy use and running costs

A UPS uses energy as conversion and charging losses on top of what your equipment consumes. The EXR Series 90000966 has an ENERGY STAR weighted efficiency of 98.5%. The table estimates its losses if it supports a steady load 24 hours a day, 365 days a year, at $0.17 per kWh.

Losses calculated from the efficiency measured at each load point in the minimum tested configuration.
LoadEfficiencyPower lostLosses per yearCost per year
25% (225 W)96.9%7.2 W63 kWh$10.72
50% (450 W)98.3%7.78 W68 kWh$11.59
75% (675 W)98.5%10.3 W90 kWh$15.31
100% (900 W)98.5%13.7 W120 kWh$20.41

Even with nothing connected, the UPS draws about 6.35 W to keep its electronics and battery charger running — around 56 kWh ($9.46) a year.

Loading a UPS very lightly lowers its efficiency, so choosing a unit sized reasonably close to your actual load keeps losses down.

Frequently asked questions

How much equipment can the EXR Series 90000966 power?

It is rated at 900 W (1,000 VA). Keep the connected load below that — ideally under about 720 W — to allow for surges and battery aging.

How long will the EXR Series 90000966 run on battery?

The certification record lists 5 minutes at full load and 17 minutes at half load. Lighter loads run longer; older or warm batteries run shorter.

What type of UPS is the EXR Series 90000966?

It uses a standby (offline) topology and defaults to VFD (voltage and frequency dependent) operation. Standby designs are compact and economical for desktop computers and home networks.

How efficient is the EXR Series 90000966?

Its ENERGY STAR weighted efficiency is 98.5%. At half load (450 W) it is 98.3% efficient, losing about 7.78 W — roughly $11.59 a year if run continuously at $0.17/kWh.

How many outlets does the EXR Series 90000966 have?

It has 8 outlets, all of which provide battery backup and surge protection.

Can the EXR Series 90000966 be monitored over the network?

Yes. It has an Ethernet connection and supports HTTP and SNMP.

Sources and disclaimer

Specifications on this page come from the ENERGY STAR certified ups battery backups dataset published by the U.S. Environmental Protection Agency (record certified November 30, 2020), retrieved October 7, 2026.

The setup, operating, maintenance and troubleshooting guidance is written by ManualHarbor's editors for this specific product type and configuration. It is an independent guide — not a reproduction of the manufacturer's manual — and ManualHarbor is not affiliated with EXR Series. Always follow the safety instructions, installation requirements and warranty terms supplied with your unit, and contact EXR Series or an authorized service provider for warranty repairs and replacement parts.

Running-cost figures use assumed U.S. average utility prices and are estimates for comparison only. See our editorial methodology for details.