Ups 650va Tescom Leo Plus Lcd 650ap With Usb Port Tower New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Voltage: 100 / 110 / 120 V: 80 - 150 Vac, 220 / 230 / 240 V: 162 - 295 Vac (145 - 295 Vac optional)
Frequency: 50 / 60 Hz + - 10% (auto-sensing)
[[OUTPUT]]
Voltage: 100 / 110 / 120 Vac + - 10% or 220 / 230 / 240 Vac + - 10%
Frequency: 50 / 60 Hz + - 1% (auto-sensing)
Waveform: Mains mode: pure sine wave Battery mode: simulated sine wave
Transfer time: Typical 2 - 7 ms, 10 ms max.
[[BATTERIES]]
DC voltage: 12 V
Configuration: 12 V / 7 Ah x 1
Recharge time: 6 - 8 h
[[COMMUNICATIONS]]
USB (optional): Supports Windows 98 / 2000 / 2003 / XP / Vista / 2008 / Windows?7 / 8 / 10
[[OTHER SPECS]]
Protections: Short circuit - battery overcharge , overdischarge , overload - surge
Humidity: 20 - 90% RH @ 0- 40 (non-condensing)
Noise level: <= 40 dB (1 m)
Plastic Case: Net / Gross weight (kg) 4.2 / 4.6, Dimensions 90 x 305 x 165, Packaged dimensions: 133 x 349 x 232, Quantity /20ft 2300 pcs
Ups 850va Tescom Leo Plus Led 850a W/o Port Tower New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Voltage: 100 / 110 / 120 V: 80 - 150 Vac, 220 / 230 / 240 V: 162 -295 Vac (145 -295 Vac optional)
Frequency: 50 / 60 Hz + - 10% (auto-sensing)
[[OUTPUT]]
Voltage: 100 / 110 / 120 Vac + - 10% or 220 / 230 / 240 Vac + - 10%
Frequency: 50 / 60 Hz+ - 1% (auto-sensing)
Waveform: Mains mode: pure sine wave Battery mode: simulated sine wave
Transfer time: Typical 2 -7 ms, 10 ms max.
[[BATTERIES]]
DC voltage: 12 V
Configuration: 12 V / 9 Ah x 1
Recharge time: 6 - 8 h
[[COMMUNICATIONS]]
USB (optional): Supports Windows 98 / 2000 / 2003 / XP / Vista / 2008 / Windows7 / 8 / 10
[[OTHER SPECS]]
Protections: hort circuit - battery overcharge - overdischarge - overload - surge
Humidity: 20 -90% RH @ 0 - 40 (non-condensing)
Noise level: <= 40 dB (1 m)
Plastic Case: Net / Gross weight (kg) 5.0 / 5.4, Dimensions 90 Χ 305 Χ 165, Packaged dimensions: 133 x 349 x 232, Quantity /20ft 2300 pcs
Ups 850va Tescom Leo Plus Lcd 850ap With Usb Port Tower New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Voltage: 100 / 110 / 120 V: 80 - 150 Vac, 220 / 230 / 240 V: 162 - 295 Vac (145 - 295 Vac optional)
Frequency: 50 / 60 Hz + - 10% (auto-sensing)
[[OUTPUT]]
Voltage: 100 / 110 / 120 Vac + - 10% or 220 / 230 / 240 Vac + - 10%
Frequency: 50 / 60 Hz + - 1% (auto-sensing)
Waveform: Mains mode: pure sine wave Battery mode: simulated sine wave
Transfer time: Typical 2 - 7 ms, 10 ms max.
[[BATTERIES]]
DC voltage: 12 V
Configuration: 12 V / 9 Ah x 1
Recharge time: 6 - 8 h
[[COMMUNICATIONS]]
USB (optional): Supports Windows? 98 / 2000 / 2003 / XP / Vista / 2008 / Windows?7 / 8 / 10
[[OTHER SPECS]]
Protections: Short circuit - battery overcharge - overdischarge - overload - surge
Humidity: 20 - 90% RH @ 0- 40 (non-condensing)
Noise level: <= 40 dB (1 m)
Plastic Case: Net / Gross weight (kg) 5.0 / 5.4, Dimensions 90 ? 305 ? 165, Packaged dimensions: 133 x 349 x 232, Quantity /20ft 2300 pcs
Ups 1200va Tescom Leo Plus Lcd 1200ap With Usb P Tower New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Voltage: 100 / 110 / 120 V: 80 - 150 Vac, 220 / 230 / 240 V: 162 - 295 Vac (145 - 295 Vac optional)
Frequency: 50 / 60 Hz + - 10% (auto-sensing)
[[OUTPUT]]
Voltage: 100 / 110 / 120 Vac + - 10% or 220 / 230 / 240 Vac + - 10%
Frequency: 50 / 60 Hz + - 1% (auto-sensing)
Waveform: Mains mode: pure sine wave Battery mode: simulated sine wave
Transfer time: Typical 2 - 7 ms, 10 ms max.
[[BATTERIES]]
DC voltage: 24 V
Configuration: 12 V / 7 Ah x 2
Recharge time: 6 - 8 h
[[COMMUNICATIONS]]
USB (optional): Supports Windows? 98 / 2000 / 2003 / XP / Vista / 2008 / Windows?7 / 8 / 10
[[OTHER SPECS]]
Protections: Short circuit - battery overcharge - overdischarge - overload - surge
Humidity: 20 - 90% RH @ 0- 40 (non-condensing)
Noise level: <= 40 dB (1 m)
Plastic Case: Net / Gross weight (kg) 9.4 / 9.9, Dimensions 115 x 320 x 220, Packaged dimensions: 161 x 369 x 290, Quantity /20ft 1400 pcs
Ups 1500va Tescom Leo Plus Lcd 1500ap With Usb P Tower New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Voltage: 100 / 110 / 120 V: 80 - 150 Vac, 220 / 230 / 240 V: 162 - 295 Vac (145 - 295 Vac optional)
Frequency: 50 / 60 Hz + - 10% (auto-sensing)
[[OUTPUT]]
Voltage: 100 / 110 / 120 Vac + - 10% or 220 / 230 / 240 Vac + - 10%
Frequency: 50 / 60 Hz + - 1% (auto-sensing)
Waveform: Mains mode: pure sine wave Battery mode: simulated sine wave
Transfer time: Typical 2 - 7 ms, 10 ms max.
[[BATTERIES]]
DC voltage: 24 V
Configuration: 12 V / 9 Ah x 2
Recharge time: 6 - 8 h
[[COMMUNICATIONS]]
USB (optional): Supports Windows? 98 / 2000 / 2003 / XP / Vista / 2008 / Windows?7 / 8 / 10
[[OTHER SPECS]]
Protections: Short circuit - battery overcharge - overdischarge - overload - surge
Humidity: 20 - 90% RH @ 0- 40 (non-condensing)
Noise level: <= 40 dB (1 m)
Plastic Case: Net / Gross weight (kg) 9.8 / 10.3, Dimensions 115 x 320 x 220, Packaged dimensions: 161 x 369 x 290, Quantity /20ft 1400 pcs
Ups 2000va Tescom Leo Plus Lcd Usb Port Tower New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Voltage: 100 / 110 / 120 V: 80 - 150 Vac, 220 / 230 / 240 V: 162 - 295 Vac (145 - 295 Vac optional)
Frequency: 50 / 60 Hz + - 10% (auto-sensing)
[[OUTPUT]]
Voltage: 100 / 110 / 120 Vac + - 10% or 220 / 230 / 240 Vac + - 10%
Frequency: 50 / 60 Hz + - 1% (auto-sensing)
Waveform: Mains mode: pure sine wave Battery mode: simulated sine wave
Transfer time: Typical 2 - 7 ms, 10 ms max.
[[BATTERIES]]
DC voltage: 24 V
Configuration: 12 V / 9 Ah x 2
Recharge time: 6 - 8 h
[[COMMUNICATIONS]]
USB (optional): Supports Windows? 98 / 2000 / 2003 / XP / Vista / 2008 / Windows?7 / 8 / 10
[[OTHER SPECS]]
Protections: Short circuit - battery overcharge - overdischarge - overload - surge
Humidity: 20 - 90% RH @ 0- 40 (non-condensing)
Noise level: <= 40 dB (1 m)
Metal Case: Net / Gross weight (kg) 12.9 / 13.3, Dimensions 25 x 380 x 225, Packaged dimensions: 161 x 369 x 290, Quantity /20ft 1000 pcs
Ups 2000va Tescom Leo Plus Lcd Usb Port Tower neo
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Voltage: 100 / 110 / 120 V: 80 - 150 Vac, 220 / 230 / 240 V: 162 - 295 Vac (145 - 295 Vac optional)
Frequency: 50 / 60 Hz + - 10% (auto-sensing)
[[OUTPUT]]
Voltage: 100 / 110 / 120 Vac + - 10% or 220 / 230 / 240 Vac + - 10%
Frequency: 50 / 60 Hz + - 1% (auto-sensing)
Waveform: Mains mode: pure sine wave Battery mode: simulated sine wave
Transfer time: Typical 2 - 7 ms, 10 ms max.
[[BATTERIES]]
DC voltage: 24 V
Configuration: 12 V / 9 Ah x 2
Recharge time: 6 - 8 h
[[COMMUNICATIONS]]
USB (optional): Supports Windows? 98 / 2000 / 2003 / XP / Vista / 2008 / Windows?7 / 8 / 10
[[OTHER SPECS]]
Protections: Short circuit - battery overcharge - overdischarge - overload - surge
Humidity: 20 - 90% RH @ 0- 40 (non-condensing)
Noise level: <= 40 dB (1 m)
Metal Case: Net / Gross weight (kg) 12.9 / 13.3, Dimensions 25 x 380 x 225, Packaged dimensions: 161 x 369 x 290, Quantity /20ft 1000 pcs
Ups 1000va Tescom 1101st Neoline St Pro Tower New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Rated voltage: 208 V / 220 V / 230 V / 240 Vac
Voltage range: 110 - 176 Vac (linear derating between 50% and 100% load ), 176 - 280 Vac (no derating), 280 - 300 Vac (derating 50%)
Frequency: 40 - 70 Hz (auto-sense)
Power factor: >= 0.99
Bypass voltage range: 25% +15% (settable)
Total Harmonic Distortion (THDi) <= 6%
[[OUTPUT]]
Voltage: 208 V / 220 V / 230 V / 240 Vac (settable via LCD)
Voltage regulation : 1 +-
Waveform: Sinusoidal
Crest factor: <= 2% (linear load); <= 5% (non-linear load)
Transfer time: Mains mode to battery mode: 0 ms, Inverter mode to bypass mode: 4 ms (typical)
Overload capability: 105% - 125%: transfer to bypass in 1 min, 125% - 150%: transfer to bypass in 30 s, > 150%: transfer to bypass in 300 ms
[[EFFICIENCY]]
Mains mode: >= 90%
Battery mode: >= 85%
ECO mode: >= 95%
[[BATTERIES]]
DC voltage: 24 V
Inbuilt battery: 2 x12v 9Ah
Charging current (max.): 1A
Recharge time : 8 h
TYPE: VRLA sealed lead acid maintenance free
ALARMS: On Utility failure / Low battery / Overload / UPS fault
[[COMMUNICATIONS]]
RS232 (standard) / USB (optional) : Supports Windows? 98 / 2000 / 2003 / XP / Vista / 2008 / Windows? 7 / 8 / 10
SNMP (optional): Power management from SNMP manager and web browser
[[OTHER SPECS]]
Output Power Plugs: 2 Schuko (3 IEC optional)
Operating temperature: 0 - 40
Storage temperature: from -40 to 70 °C (without batteries)
Relative Humidity: 0 - 95% (non-condensing)
Altitude: <= 1000m, derating 1% for each additional 100m
IP rating: IP20
Noise level: <= 50 dB (1m)
Dimensions: 144x336x214
Packaged dimensions: 232x417x318
Net weight (kg): 9.5
Ups 3000va 1103st Tescom Neoline St Pro Tower New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Rated voltage: 208 V / 220 V / 230 V / 240 Vac
Voltage range: 110 - 176 Vac (linear derating between 50% and 100% load ), 176 - 280 Vac (no derating), 280 - 300 Vac (derating 50%)
Frequency: 40 - 70 Hz (auto-sense)
Power factor: >= 0.99
Bypass voltage range: 25% +15% (settable)
Total Harmonic Distortion (THDi) <= 6%
[[OUTPUT]]
Voltage: 208 V / 220 V / 230 V / 240 Vac (settable via LCD)
Voltage regulation : 1 +-
Frequency: 45- 55 Hz or 55 - 65 Hz (synchronized range), 50 / 60 Hz + - 0.1 Hz (battery mode)
Waveform: Sinusoida
Crest factor: 3:01
Harmonic distortion: <= 2% (linear load); <= 5% (non-linear load)
Transfer time: Mains mode to battery mode: 0 ms, Inverter mode to bypass mode: 4 ms (typical)
Overload capability: 105% - 125%: transfer to bypass in 1 min, 125% - 150%: transfer to bypass in 30 s, > 150%: transfer to bypass in 300 ms
[[EFFICIENCY]]
Mains mode: >= 92%
Battery mode: >= 87%
ECO mode: >= 97%
[[BATTERIES]]
DC voltage: 72 V
Inbuilt battery: 6 x 12v 9Ah
Charging current (max.): 1A
Recharge time : 8 h
TYPE: VRLA sealed lead acid maintenance free
ALARMS: On Utility failure / Low battery / Overload / UPS fault
[[COMMUNICATIONS]]
RS232 (standard) / USB (optional) : Supports Windows? 98 / 2000 / 2003 / XP / Vista / 2008 / Windows? 7 / 8 / 10
SNMP (optional): Power management from SNMP manager and web browser
[[OTHER SPECS]]
Output Power Plugs: 4 Schuko (6 IEC optional)
Operating temperature: 0 - 40°C
Storage temperature: from -40 to 70 °C (without batteries)
Relative Humidity: 0 - 95% (non-condensing)
Altitude: <= 1000m, derating 1% for each additional 100m
IP rating: IP20
Noise level: <= 50 dB (1m)
Dimensions: 191x464x335
Packaged dimensions: 320x573x471
Net weight (kg): 32
Ups 2000va 1102srt Tescom Neoline Srt Pro Tower/rack New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Rated voltage: 208 / 220 / 230 / 240 Vac
Voltage range: "110 -176 Vac (linear derating between 50% and 100% load), 176 - 280 Vac (no derating), 280 - 300 Vac (derating
50%)"
Frequency: 40 - 70 Hz (auto-sense)
Power factor: >= 0.99
Bypass voltage range: - 25% + 15% settable
Total Harmonic Distortion (THDi) <= 6%
[[OUTPUT]]
Voltage: 208 / 220 / 230 / 240 Vac (settable via LCD)
Voltage regulation : 1 +-
Frequency: 45 - 55 Hz or 55 - 65 Hz (synchronized range); 50 / 60 Hz + - 0.1 Hz (battery mode)
Waveform: Sinusoidal
Power factor: 0.9
Total harmonic distortion (THDv): <= 2% (linear load), <= 5% (non-linear load
Crest factor: 3:1
Overload: 105% - 125% for 1 min, 125% - 150% for 30 s, > 150% for 300 ms
[[BATTERIES]]
DC voltage: 48 V (S)
Inbuilt battery: 4 x 9 Ah
Charging current (max.): 1A
Recharge time : Standard model: 90% capacity restored in 4 hours, Long time model: depend on the capacity of battery
[[SYSTEM]]
Efficiency: >= 90% (Mains mode), >= 85% (Battery mode), >= 95% (ECO mode)
Transfer time: Mains mode to battery mode: 0 ms, Inverter mode to bypass mode: 4 ms (typical)
Protections: Short-circuit, overload, overtemperature, battery discharge protection and fan testing protection
Communications: RS232 (standard), USB / RS485 / dry contacts / SNMP (optional)
Display: LCD + LED
Standards: "EN 62040-1, EN 62040-2, EN 61000-3-2, EN 61000-3-3, IEC 61000-4-2, IEC 61000-4-3, IEC 61000-4-4, IEC
61000-4-5, IEC 61000-4-6, IEC 61000-4-8, IEC 61000-4-11, IEC 61000-2-2, IEC 62040-2, IEC 62040-1"
[[OTHER SPECS]]
Operating temperature: 0 - 40°C
Storage temperature: from -25 to 55 °C (without batteries)
Relative Humidity: 0 - 95% (non-condensing)
Altitude: <= 1000 m, derating 1% for each additional 100 m
IP rating: IP 20
Noise level at 1m: <= 50 Db
Dimensions: 440 x 430 x 88
Packaged dimensions: 545 x 560 x 201
Net weight (kg): 18.7
Gross weight (kg): 21.8
Ups 3kva 1103srt Tescom Neoline Srt Pro Tower/rack New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Rated voltage: 208 / 220 / 230 / 240 Vac
Voltage range: "110 -176 Vac (linear derating between 50% and 100% load), 176 - 280 Vac (no derating), 280 - 300 Vac (derating
50%)"
Frequency: 40 - 70 Hz (auto-sense)
Power factor: >= 0.99
Bypass voltage range: - 25% + 15% settable
Total Harmonic Distortion (THDi) <= 6%
[[OUTPUT]]
Voltage: 208 / 220 / 230 / 240 Vac (settable via LCD)
Voltage regulation : 1 +-
Frequency: 45 - 55 Hz or 55 - 65 Hz (synchronized range); 50 / 60 Hz + - 0.1 Hz (battery mode)
Waveform: Sinusoidal
Power factor: 0.9
Total harmonic distortion (THDv): <= 2% (linear load), <= 5% (non-linear load
Crest factor: 3:1
Overload: 105% - 125% for 1 min, 125% - 150% for 30 s, > 150% for 300 ms
[[BATTERIES]]
DC voltage: 72 V (S)
Inbuilt battery: 6 x 9 Ah
Charging current (max.): 1A
Recharge time : Standard model: 90% capacity restored in 4 hours, Long time model: depend on the capacity of battery
[[SYSTEM]]
Efficiency: >= 92% (Mains mode), >= 87% (Battery mode), >= 97% (ECO mode)
Transfer time: Mains mode to battery mode: 0 ms, Inverter mode to bypass mode: 4 ms (typical)
Protections: Short-circuit, overload, overtemperature, battery discharge protection and fan testing protection
Communications: RS232 (standard), USB / RS485 / dry contacts / SNMP (optional)
Display: LCD + LED
Standards: "EN 62040-1, EN 62040-2, EN 61000-3-2, EN 61000-3-3, IEC 61000-4-2, IEC 61000-4-3, IEC 61000-4-4, IEC
61000-4-5, IEC 61000-4-6, IEC 61000-4-8, IEC 61000-4-11, IEC 61000-2-2, IEC 62040-2, IEC 62040-1"
[[OTHER SPECS]]
Operating temperature: 0 - 40°C
Storage temperature: from -25 to 55 °C (without batteries)
Relative Humidity: 0 - 95% (non-condensing)
Altitude: <= 1000 m, derating 1% for each additional 100 m
IP rating: IP 20
Noise level at 1m: <= 50 Db
Dimensions: 440 x 560 x 88
Packaged dimensions: 545 x 690 x 201
Net weight (kg): 26.8
Gross weight (kg): 29.7
Ups 1102srt Tescom Prime Plus 2kva/2000w Rack Type Lcd New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Nominal Voltage: 200/208/220/230/240 VAC
Voltage range: 110-300 VAC +- 5% 50% load, 160-300 VAC +- 5% 100% load
Frequency range: 40 - 70 Hz
Total Harmonic Distortion (THDi) <= 5% nominal input voltage
Power factor: >= 0.99 nominal voltage (100% load)
[[OUTPUT]]
Output Voltage: 200*/208*/220/230/240 VAC
AC Voltage Regulation: = +- 1%
Frequency Range: 57 ~ 63 Hz or 47 ~ 53 Hz
Current Crest Ratio: 3:1 max
Harmonic Distortion: <= 2 % THD (Linear Load), <= 4 % THD (Non-linear load)
Transfer Time: AC mode to Battery mode= Zero, Inverter to Bypass= 4 ms (Typical)
Waveform: Pure Sinewave
Overload: 110-130% 5 min / 130-140% 30 sec / >140% 1.5 sec to 100ms
Outlets: 8 x IEC 320 C13
[[EFFICIENCY]]
AC Mode: >= 90% full charged battery
ECO Mode: >=96% @ full charged battery
Battery Mode: >= 88%
[[BATTERIES]]
Battery Type (VRLA): 12 V / 9 AH
Numbers: 6
Typical Recharge Time: 3 hours recover to 95% capacity for internal battery 2A charging current
Charging Current: Default 2A, max. 12A adjustable
Charging Voltage: 54.8 VDC -+ 1%
[[PHUSICAL]]
Dimension, D x W x H (mm): 510 x 438 x 88
Net Weight (without battery) (kgs): 9.4
Net Weight (w/built-int battery) (kgs): 19.5
[[ENVIRONMENT]]
Humidity: 5-95 % RH , 0- 40 (non-condensing)
Noise Level: Less than 50dBA, 1 Meter
Altitude: 10% de-rating for over 1000m (The altitude should not exceed 3000m)
[[MANAGMENT]]
Smart RS-232/USB & Softwarel: Supports Windows 2000/2003/ XP/ Vista/ 2008/ 7/ 8, Linux and MAC
Optional SNMPl: Power management from SNMP manager and web browser
[[STANDARD]]
EMC/safety: EMC EN62040-2 C2 / EN 62040 - 1 / EN 62040 ? 3 / RoHS 2
Ups 3kva 1103srt Tescom Prime Plus Tower/rack New
Διαθέσιμο σε 4 εως 10 ημερες
[[INPUT]]
Nominal Voltage: 200/208/220/230/240 VAC
Voltage range: 110-300 VAC +- 5% 50% load, 160-300 VAC +- 5% 100% load
Frequency range: 40 - 70 Hz
Total Harmonic Distortion (THDi) <= 5% nominal input voltage
Power factor: >= 0.99 nominal voltage (100% load)
[[OUTPUT]]
Output Voltage: 200*/208*/220/230/240 VAC
AC Voltage Regulation: = +- 1%
Frequency Range: 57 ~ 63 Hz or 47 ~ 53 Hz
Current Crest Ratio: 3:1 max
Harmonic Distortion: <= 2 % THD (Linear Load), <= 4 % THD (Non-linear load)
Transfer Time: AC mode to Battery mode= Zero, Inverter to Bypass= 4 ms (Typical)
Waveform: Pure Sinewave
Overload: 110-130% 5 min / 130-140% 30 sec / >140% 1.5 sec to 100ms
Outlets: 8 x IEC 320 C13 + 1 x IEC 320 C19
[[EFFICIENCY]]
AC Mode: >= 91% @ full charged battery
ECO Mode: >=96% @ full charged battery
Battery Mode: >= 90%
[[BATTERIES]]
Battery Type (VRLA): 12 V / 9 AH
Numbers: 6
Typical Recharge Time: 3 hours recover to 95% capacity for internal battery 2A charging current
Charging Current: Default 2A, max. 12A adjustable
Charging Voltage: 82.1 VDC -+ 1%
[[PHUSICAL]]
Dimension, D x W x H (mm): 630 x 438 x 88
Net Weight (without battery) (kgs): 12,4
Net Weight (w/built-int battery) (kgs): 27,5
[[ENVIRONMENT]]
Humidity: 5-95 % RH , 0- 40 (non-condensing)
Noise Level: Less than 50dBA, 1 Meter
Altitude: 10% de-rating for over 1000m (The altitude should not exceed 3000m)
[[MANAGMENT]]
Smart RS-232/USB & Softwarel: Supports Windows 2000/2003/ XP/ Vista/ 2008/ 7/ 8, Linux and MAC
Optional SNMPl: Power management from SNMP manager and web browser
[[STANDARD]]
EMC/safety: EMC EN62040-2 C2 / EN 62040 - 1 / EN 62040 3 / RoHS 2