The APC Smart-UPS RC 800W 1KVA Sine Wave SRC1KI provides reliable backup power for critical devices. First, it delivers pure sine wave output, ideal for sensitive electronics. In addition, the UPS protects connected equipment from power surges, spikes, and outages. Moreover, it features a compact design for easy placement in offices or server rooms. Finally, the unit includes an intuitive LCD interface for monitoring battery status and load. The SRC1KI ensures continuous operation and safeguards important systems during power interruptions. Specifications: 800W / 1KVA pure sine wave output for sensitive devices Protects against power surges, spikes, and outages Compact design for office or server room placement LCD interface for monitoring battery and load status Ensures continuous operation during power interruptions
Aokly Gel Battery 12V – 200A 58.5Kg manufacturer link
The Beco GP1500 1500VA 900W UPS delivers strong and reliable power protection for home and office electronics. It keeps computers, routers, and monitors running during outages. This helps prevent data loss and sudden shutdowns. Peace of mind increases with reliable backup power. Moreover, the Beco GP1500 1500VA 900W UPS offers 1500 VA capacity and 900 W output for high-demand systems. It supports larger desktops and entertainment setups easily. Backup power stays strong during interruptions. This improves system stability every day. In addition, the UPS features built-in surge protection to guard appliances from spikes and unstable power. This adds important defense against electrical damage. Devices remain safe during storms and fluctuations. Safety stays consistent. Furthermore, the Beco GP1500 1500VA 900W UPS includes automatic voltage regulation to smooth dips and spikes. It balances voltage without manual adjustment. This helps extend device lifespan. Consistent power improves performance. Also, the UPS delivers dependable battery backup when electricity fails. You can save files and shut down properly before power runs out. This reduces the risk of data loss. Backup support feels reassuring. In addition, the Beco GP1500 1500VA 900W UPS has clear LED indicators for power and battery status. You can check conditions easily at a glance. This makes monitoring simple and fast. Moreover, the UPS includes multiple output sockets for connecting several devices at once. This increases flexibility for busy workstations and entertainment centers. You can protect all critical electronics with one unit. Furthermore, the Beco GP1500 1500VA 900W UPS supports quick plug-and-play setup with no complex steps. Installation feels easy for any user. Setup remains fast and hassle-free. Also, the compact and sturdy design fits neatly into workspaces or shelves. It blends well into home and office environments. Portability stays practical. Overall, the Beco GP1500 1500VA 900W UPS delivers strong battery backup, surge protection, and voltage regulation. It ensures steady power and protects electronics effectively. This UPS is ideal for users needing reliable, high-capacity power protection every day. Specifications: 1500VA, 900W, LED, Plastic Case Input: 140-290 VAC Output: 230VAC 50/60HZ 12V 9AH *2pcs, Universal Socket *4 + EU Plug With AVR, Bypass output Overload and short circuit protection
The PROLINK PRO700 Line Interactive UPS is designed to provide reliable backup power and protection for computers, networking devices, and other electronic equipment. It helps maintain stable operation during power interruptions and voltage fluctuations. With a 650VA capacity and 360W output power, this UPS provides practical power support for home and office environments. Additionally, its line-interactive design with AVR technology helps regulate voltage and improve power stability. The PRO700 supports a wide input voltage range from 140V to 300V AC. Moreover, it automatically senses 50Hz or 60Hz input frequency, allowing compatibility with different power environments. The UPS provides simulated sine wave output during battery mode and sine wave output during AC mode. Furthermore, the fast transfer time helps reduce interruptions when switching to battery operation. The built-in 12V 8.2Ah battery provides backup power for connected devices during outages. Therefore, users can safely save work and shut down equipment during unexpected power failures. The PROLINK PRO700 includes protection features against short circuits, overloads, discharge, and overcharge conditions. In addition, its intelligent battery management helps improve battery protection and lifespan. The compact design makes the UPS suitable for desktops, network equipment, and small office setups. Also, its low noise operation allows comfortable use in different working environments. The PROLINK PRO700 Line Interactive UPS combines voltage regulation, backup power, and essential protection features in a compact solution. As a result, it provides dependable power support for everyday electronic devices. Specifications: Capacity: 650VA / 360W Input Voltage Range: 140V–300V AC ±5% Battery: 12V / 8.2Ah sealed lead-acid battery Output Waveform: Simulated sine wave (Battery Mode) Protection: Short circuit, overload, discharge, and overcharge protection
PCE CASA 1KVA inverter is a compact off-grid power solution designed for home and small office backup use. It helps keep essential devices running during power cuts, such as routers, lights, and small electronics. In addition, it provides pure sine wave output. Therefore, it delivers clean and stable power for sensitive devices. Moreover, it supports AC mains and generator input, which makes it flexible in different power conditions. Furthermore, PCE CASA 1KVA inverter includes smart battery charging control. As a result, it improves charging efficiency and helps extend battery life. It also supports automatic restart after power recovery, ensuring continuous operation. In addition, it includes built-in protection features. Therefore, it helps protect against overload, short circuit, and overheating. Moreover, it supports a cold start function for direct battery operation when no grid power is available. Overall, PCE CASA 1KVA inverter delivers reliable backup performance, stable output, and essential protection for everyday home and office energy needs. Specifications: 1KVA capacity for home and small office loads Pure sine wave output for stable device operation AC mains and generator input support Smart battery charging control for efficiency Built-in protection against overload and short circuit
The PCE PCD 12V 65Ah Deep Cycle Battery delivers dependable power for a wide range of applications. It provides stable energy over long discharge cycles. This battery supports regular use in marine, RV, solar, and backup power systems. It fits well where lasting performance matters. Moreover, the PCE PCD Deep Cycle Battery features a deep cycle design for long life and strong reliability. It tolerates repeated charging and discharging without damage. This increases uptime and reduces maintenance needs. Users enjoy continuous power without frequent replacements. In addition, the battery delivers 12 V and 65 Ah capacity for steady power delivery. This suits medium and high demand systems. Appliances, lights, and electronics receive reliable current. It helps systems stay stable in everyday use. Furthermore, the PCE PCD 12V 65Ah Deep Cycle Battery includes sturdy construction for long-lasting durability. The strong casing protects internal cells against wear and tear. This adds confidence in heavy use environments. Performance remains consistent over time. Also, the battery supports deep discharge recovery for extended service life. It recovers well even after heavy drain cycles. In addition, the PCE PCD Deep Cycle Battery is easy to install in many setups. It fits most battery holders and racks without fuss. Connections remain secure and simple. Furthermore, the PCE PCD Deep Cycle Battery supports stable performance in varying temperatures. It remains reliable in moderate heat and cold. This helps outdoor and mobile applications. Overall, the PCE PCD 12V 65Ah Deep Cycle Battery delivers strong power, lasting durability, and smooth performance. It fits home, marine, solar, and backup use. This battery is ideal for users who want dependable deep cycle energy every day. Specifications: Voltage : 12V Capacity : 65Ah
UPS battery 12V 7A Battery for UPS 7A 12v
The Twist Online High Frequency UPS 6KVA TWUP6000/HF provides continuous backup power for servers, networking systems, and critical equipment. It uses online double conversion technology for stable and clean power delivery. Additionally, the high-frequency design improves efficiency and reduces transfer interruptions. Moreover, the UPS includes an LCD display for real-time monitoring and system alerts. It features internal 16x12V/9Ah batteries for backup operation during outages. Therefore, it protects connected devices from voltage fluctuations, overloads, and sudden power loss. Furthermore, the TWUP6000/HF supports pure sine wave output for sensitive electronic equipment. It also includes overload, short-circuit, and overheating protection for safer operation. Additionally, the tower design fits office, server room, and IT environments easily. Specifications: 6KVA online double conversion UPS technology Internal 16x12V/9Ah rechargeable batteries LCD display for real-time monitoring Pure sine wave output for stable power delivery Overload and short-circuit protection system
The Beco GP2000 2000VA 1200W UPS delivers dependable power protection for home, office, and business systems. It supports high-demand devices like desktops, servers, and networking equipment. This UPS helps prevent data loss and sudden shutdowns during power interruptions. Users enjoy peace of mind with reliable backup. Moreover, the Beco GP2000 2000VA 1200W UPS features a 2000 VA capacity and 1200 W output power for strong performance. It maintains stable power for multiple connected devices. This helps keep critical systems running longer during outages. Reliability stays consistent. In addition, the UPS includes built-in surge protection for safe operation against voltage spikes. It guards your electronics from unpredictable power surges. This adds extra defense during storms or unstable conditions. Device safety remains a priority. Furthermore, the Beco GP2000 2000VA 1200W UPS offers automatic voltage regulation to smooth dips and spikes. It balances fluctuating power automatically. This strengthens system reliability and helps extend equipment life. Power stays steady without manual changes. Also, the UPS provides battery backup when electricity fails. You can save work and shut down systems properly before power runs out. This reduces risk of data corruption. Backup power feels dependable and secure. In addition, the Beco GP2000 2000VA 1200W UPS includes easy-to-read LED indicators for power and battery status. You can check conditions at a glance. This makes monitoring clear and simple. Users stay informed during operation. Moreover, the UPS supports multiple output sockets for connecting several devices simultaneously. This increases flexibility for desks, workstations, and server setups. You can protect many electronics at once. Furthermore, the Beco GP2000 2000VA 1200W UPS supports easy installation with plug-and-play setup. Connections are marked clearly for simple use. Setup remains quick and stress-free. Also, the compact and sturdy design fits neatly on desks or shelves. It blends into home and office spaces easily. Portability stays practical. Overall, the Beco GP2000 2000VA 1200W UPS delivers strong battery backup, surge protection, and smooth voltage regulation. This UPS is perfect for users needing powerful and reliable power protection every day. Specifications: 2000VA, 1200W, LCD, Plastic Case Input: 140-290 VAC Output: 230VAC 50/60HZ 12V 9AH *2pcs, Universal Socket *4 + EU Plug With AVR, Bypass output Overload and short circuit protection
Features • Advanced DSP and 3-level technology • Output power factor 1.0 • Active power factor correction (APFC), input power factor up to 0.99 • High efficiency 95% (up to 98% in ECO mode) • Advanced digital parallel technology • Wide input voltage range (11 0 – 288 Vac) and frequency range (40 -70Hz) • 50 I 60 Hz frequency auto sensing • Two modes of frequency conversion: 50 Hz input I 60 Hz output or 60 Hz input I 50 Hz output • Dual-input design, supporting independent bypass • Flexible battery configuration (settable 16-20 pes batteries) • Digitally controlled charger • High charging current available (Max. 12 A) • Charging voltage and current configured by demands • Linear derating in low voltage input reducing battery discharging times, extending the service life of battery • Intelligent battery management, automatic floating I equalizing charge control, charger dormancy control, increasing battery life by 50%• Ability to switch on the UPS with batteries • Settable delayed start time when mains power is restored, reducing the impact on power grid or generator • Fan speed varies intelligently with temperature, reducing noise and extending its service life • Equipped with self-aging function • Compact internal layout, miniaturized the complete unit for small footprint • LCD+LED display, multi-functional keys operation, friendly human-machine interface • Powerful background software for parameters configuration • Advanced multi-platform communications: RS232, USB, RS485, SNMP and dry contacts communication interfaces • Effective software and hardware protection function, robust self-diagnostic function, and abundant event log for check Available Options • RS232 and smart card slot included • Optional parallel function, battery temperature compensation, SNMP card, USB, RS485 card, dry contacts, EMD, and SMS alarms Rear Panel 1. RS232 2. EPO 3. Parallel Port (optional) 4. USB (optional) 5. Temperature Detection (optional) 6. Intelligent Slot 7. Reserved: for manual bypass or battery breaker or outlets ect. 8.Fans 9. Bypass Breaker 10. Input Breaker 11.GND 12.Terminals and Cover http://en.eastups.com/EA900G4610kVA/6754.jhtml
Specifications : GENERAL Rated Power 5000VA / 5000W Communication Interface Removable USB / RS232 / RS485 / Bluetooth / Dry-contact Dimension D x W x H (mm) 115 x 300 x 400 Net Weight (kgs) 13 INPUT Voltage 230VAC Selectable Voltage Range 170 ~ 280 VAC (For Personal Computers)90 ~ 280 VAC (For Home Appliances) Frequency Range 50Hz / 60Hz (Auto sensing) OUTPUT AC Voltage Regulation (Batt. Mode) 230VAC ± 5% Surge Power 10000VA Efficiency (Peak) 90% ~ 93% Transfer Time 15 ms (For Personal Computers)20 ms (For Home Appliances) Waveform Pure sine wave BATTERY Battery Voltage 48VDC Floating Charge Voltage 54VDC Overcharge Protection 63VDC SOLAR & AC CHARGER Solar Charger Type MPPT Maximum PV Array Open Circuit Voltage 500VDC Maximum PV Array Power 5000W MPP Range @ Operating Voltage 120VDC~450VDC Maxmum Solar Charge Current 100A Maximum AC Charge Current 100A manufacturer link
The Beco GP600 600VA 360W UPS delivers reliable power protection for home and office devices. It keeps your electronics safe during outages and voltage drops. This UPS helps prevent data loss and sudden shutdowns, providing peace of mind every day. Moreover, the Beco GP600 600VA 360W UPS features 600 VA capacity with up to 360 W output power. It supports computers, routers, modems, and monitors effortlessly. Devices continue running smoothly during short power interruptions. This improves system stability. In addition, the UPS includes built-in surge protection for safe operation. It guards connected devices against spikes and surges. This adds an extra layer of defense during storms or unstable power conditions. Safety remains a priority. Furthermore, the Beco GP600 600VA 360W UPS offers battery backup that keeps equipment running long enough to save work. This prevents data corruption during sudden outages. Users can shut down systems properly. Protection feels dependable. Also, the unit delivers stable voltage regulation without manual adjustment. It corrects fluctuations automatically. This improves device performance and lifespan. Steady power enhances everyday use. In addition, the Beco GP600 600VA 360W UPS includes easy-to-read LED indicators. They show power and battery status at a glance. Users stay informed without confusion. Monitoring becomes simple and quick. Moreover, the UPS features multiple outlets for connecting several devices at once. This increases flexibility for workstations and entertainment setups. You can protect more devices with one unit. Furthermore, the Beco GP600 600VA 360W UPS supports simple installation without complicated steps. Setup is quick with clearly marked connections. This helps both beginners and experienced users. Also, the compact design fits well on desks or shelves without taking much space. It blends into home and office environments easily. Portability stays practical. Overall, the Beco GP600 600VA 360W UPS delivers dependable battery backup, surge protection, and steady power. It protects vital electronics and supports uninterrupted use. This UPS is ideal for users seeking reliable power protection every day. Specifications: 600VA, 360W, LED, Plastic Case Input: 145-290 VAC Output: 230VAC 50/60HZ 12V 7AH *1pc, Universal Socket *2 + EU Plug With AVR, Bypass output Overload and short circuit protection
APC UPS Accessories SURT48XLBP APC Smart-UPS RT 48V 1/2KVA SURT models Battery Pack
Specifications : Brand HAWK Package Dimensions 59.2 x 54.5 x 19.8 cm; 9 Kilograms Item model number HAWK202011 Manufacturer HAWK Wattage 720 watts Are Batteries Included Yes Item Weight 9 kg
APC UPS Accessories SURTRK APC Smart-UPS RT 19″ Rail Kit 1 – 2.2KVA
Hawk Ups 1500VA Input: Phase: Single + GND. Voltage Range: 165-275V/ 82V-138V. Frequency: 50/60Hz +- 10%. Output: Voltage Range: 220/230/240/110/120V +- 10%. Wave Form: Sine wave ( Mains), Square Waves (inverter). Frequency: 50/60Hz +- 1% (Batter Mode). Crest Factor: 3:1. Transfer time: <10ms. Protection: Energy rating: 320 Joules Instantaneous response. Test Standard: IEEE 587 Cat. A&B. Noise Filtering: EMI/RFI: Full Time Suppression. Communication: RS232 or USB with PC monitoring software and cable (optional). Battery: Type: Sealed Lead-acid. Quantity: (x2) 12V8A. Backup Time: 15-20min depends on the load.
Specifications : -True Double-Conversion Online UPS – Mircoprocessor control optimizes reliability – Input power factor correction – Output Power Factor 0.80. – Wide input voltage (110V – 300V) – Converter mode available – ECO mode for enegry saving (Only available for 1 – 3 KVA) – Generator compatible – Adjustable battery number only available for 6K and up models – Smart SNMP works well with either USB or RS-232 together – Emergency power off function (EPO) only available for 6K / 10K models – Optional isolation transformer available. manufacturer link
PCE MX Online 6KVA 5400W Internal Batteries Double Conversion Online- Pure Sine Wave
APC Easy UPS On-Line SRV 10000VA 230V SRV10KI is a high-capacity online uninterruptible power supply designed for critical business infrastructure, servers, and data center environments. It provides continuous, clean, and stable power using true double-conversion technology. It delivers 10000VA / 10000W (approx.) power capacity for heavy-duty applications. Therefore, it can support multiple servers, networking equipment, and sensitive electronics during power failures or voltage fluctuations. In addition, it ensures uninterrupted operation for mission-critical systems. The UPS uses online double-conversion technology to fully isolate connected equipment from utility power disturbances. As a result, it provides consistent, regulated pure sine wave output at all times. It includes an LCD interface for real-time monitoring of system status, load, and battery conditions. Meanwhile, built-in protection features enhance system safety and operational reliability. APC designs the Easy UPS SRV series for enterprise-grade power protection. Therefore, this model is ideal for data centers, IT infrastructure, and critical business applications requiring maximum uptime. Manufacturer link Specifications: 10000VA high-capacity output Online double-conversion UPS system Pure sine wave power output LCD monitoring display Enterprise-grade power protection
APC Easy UPS On-Line SRV 3000VA 230V SRV3KI is a high-performance uninterruptible power supply designed to provide continuous power protection for servers, network equipment, data centers, and critical business systems. It uses true online double-conversion technology to deliver clean and stable power in demanding environments. The UPS provides 3000VA / 2400W power capacity. Therefore, it can support critical equipment during power outages, voltage fluctuations, and electrical disturbances. In addition, it helps maintain business continuity and equipment reliability. It features online double-conversion technology that continuously conditions incoming power. As a result, connected devices receive consistent and clean power regardless of utility power quality. The unit includes an LCD display for real-time monitoring and system management. Meanwhile, automatic bypass functionality helps maintain power delivery during specific operating conditions and maintenance events. APC designs the Easy UPS On-Line series for dependable power protection and efficient operation. Therefore, this model is ideal for servers, network infrastructure, security systems, and mission-critical applications. manufacturer link Specifications: 3000VA / 2400W power capacity Online double-conversion technology Pure sine wave output LCD status and monitoring display Reliable backup for critical systems
INVO Online INH300 Centralized server center, mainframe, network control center, computing center Full Specifications : 3KVA 2100 W Half -Load 120 -300VAC, Full -Load 165V -300VAC 45.5Hz ~ 54.5Hz 220/230/240V ± 3% Waveform True Sine wave Frequency 50/60Hz ± 0.5 Distortion <3%(linear Load); <5%(Non -linear Load) Crest Factor 3:1 Efficiency 85% Overload Capacity 110%-150%:Switch to Bypass after 1min; >150%:Shutdown afte r 200ms Short Circuit UPS output turn off and alarm RS232 ;SNMP (Optional) LCD & LED Utility, Inverter, Bypass, Battery, Load ,Battery Mode ,Frequency , UPS Fault Indicator Audible Alarm -Battery Discharge Utility Failure, Beep/4s;Battery Low, Beep/1s UPS Abnornmal Continuous Beep and Red Led On Noise <55db (1Meter) Temperature 0°C~40°C Humidity 10%~90% Optional 19 inch Rack -mount Dimension (W * D * H) mm 357 x 144 x 215 439x190x341 514X262X455 (Long Time Mode) 514x262x710 (Standard Model) Specifications: Specifications : INVO Online UPS High Frequency 3000 VA, LCD Display Inbuilt Battery 6 x 12V/7Ah AC Input 2. Bypass 3. AC Output 4. Battery 5. Fault 6. Screen 9. LCD 1. AC Input 2. Bypass 3. AC Output 4. Battery 5. Fault 6. Screen 9. LCD 1 year warranty Manufacturer Link
In the realm of uninterruptible power supplies (UPS), the Fanshine FSUPS 2000VA 900W stands out as a dependable solution, offering a robust and efficient power backup for your electronic devices. Transitioning to its key features, the UPS Fanshine FSUPS 2000VA 900W excels in providing a substantial power capacity, ensuring that your critical electronics remain powered during unexpected outages. This UPS is designed to safeguard your equipment and data. Moreover, this power supply solution impresses with its compact design, making it suitable for various settings, from home offices to small businesses. The Fanshine FSUPS seamlessly integrates into your space without compromising on performance. In addition to its functionality, the FSUPS 2000VA 900W offers versatile connectivity options, including multiple outlets for various devices. This ensures a flexible and efficient setup, protecting a range of electronics from power fluctuations. Furthermore, Fanshine’s commitment to user-friendly design is evident in the FSUPS 2000VA 900W’s easy setup and clear indicators. This ensures that users can monitor the status of their power supply effortlessly. In conclusion, the Fanshine FSUPS 2000VA 900W redefines reliability in power backup solutions, combining substantial capacity, compact design, and user-friendly features. Elevate your protection against power interruptions effortlessly with the FSUPS 2000VA 900W – your trusted solution for uninterrupted power! Specifications Model : FSUPS2000VA Input Voltage : 145VAC~290VAC Output Voltage : 195VAC~255VAC Output Wave Form : PWM/DC Output Frequency : 50Hz Backup Time : 10 to 15 minutes Noise Level : <45dB Operating Temperature : 0-45 Celsius
Vertiv Emerson Liebert itON LI32121CT00 800VA
PCE VX Online 1 KVA 800W Internal Batteries Double Conversion Online- Pure Sine Wave Model VX 1K Input Rating Voltage Frequency Voltage range Power Factor THDi 1000VA 220V, 230V, 240V, 1Ø 2Wires 40~70Hz 176-300 VAC at 100% load, 110-300 VAC at 50% load >99% <5% Ouput Active Power @ PF=0.9 Voltage (on battery) Frequency (on battery) Transfer Time Efficiency UPS Design Technology Output Wave Form Total Harmonic distortion (THD) Crest Factor 900W 220V, 230V, 240V, +/-1% (selectable output voltage), 1Ø 2Wires 50/60 Hz +/-0.2% 0 ms 93% Online double conversion design Pure Sinewave ≤3% (linear load), ≤5% (non linear load) 3:1 Protection Overload Protection Short Circuit Protection 110% for 10min, 130% for 1min, >130% for 3sec UPS output cuts off immediately using input fuse/circuit breaker protection System Display LCD indicators Load level, Battery level, AC mode, Battery mode, Bypass mode, and Fault indicators Alarm Battery mode Low battery Overload Fault Sounding every 4 second Sounding every second Sounding twice every second Continuously sounding Battery Battery Type Typical Recharge Time DC Voltage Charging Current Back up time(1/2 Load) 12V 9Ah 4 hours to 90% Full capacity 24VDC 1A 10~15 min depending on load Communication USB or RS-232 SNMP* Compatibility Interface with power management software Power Management from SNMP manager and web browser Supports Windows family, Linux, Unix and Mac Physical W x D x H mm Net Weight Kgs(lbs) 145x282x220mm 9.8Kg(21.6lb) Environment Operating Temperature Storage Temperature Altitude Audible noise Relative Humidity 0 – 40 °C / 32 ~ 104°F -20 ~ 50°C / -4 ~ 122°F 1,500 meters max <50dBA at 1 Meter 20 to 90% humidity (non-condensing) Standards & Certifications Performance Safety EMC (EMS / EMI) Design, production, & services Environment Marking & Certifications EN50091-3/IEC 62040-3 UL 1778, CE, EN 50091-1,EN 60950 (RD/), IEC 60950 IEC 61000-4-2/-3/-4/-5/-6/-8/-11, IEC 61000-3-2/-3,FCC Part 15, CISPR 22, EN 50091-2/IEC62040-2 Class A, EN 55022/B,FCC 47 part 15 – Subpart B – ISO 9001 ISO 14001 certified company CE, TUV/GS, UL, cUL, c-Tick
The APC 1600VA BX1600MI 900W UPS provides reliable backup power for home and office electronics. First, it delivers line-interactive output to protect devices from voltage fluctuations. In addition, it safeguards connected equipment from surges, spikes, and short outages. Moreover, the compact design allows easy placement near computers or servers. Finally, the LCD indicators display battery and load status for real-time monitoring. The BX1600MI-GR ensures uninterrupted operation and reliable protection for critical devices. manufacturer link Specifications: 900W / 1600VA line-interactive output for reliable device protection Protects electronics from power surges, spikes, and outages Compact design for easy placement near computers or servers LCD indicators for monitoring battery and load status Ensures uninterrupted operation during power interruptions