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S8T-DCBU-02

Buffer Block

S8T-DCBU-02

Prevents Equipment Stoppage, Data Loss,and Other Problems Resulting from Momentary Power Failures

Ratings/Characteristics

Model S8T-DCBU-02
Input Voltage 24 to 28 VDC
Current Charging 0.4 A
Standby 0.18 A
Output
*1
Backup
operation
Output voltage For 24 V: 22.5 V typ., 22.0 V min.
For 28 V: 26.4 V typ., 25.8 V min.
Output current 2.5 A
Backup time
*2
Time required until the voltage drops from the fully charged level down
to 21.6 VDC
1,000 ms min. (for an output current of 1.2 A)
500 ms min. (for an output current of 2.5 A)
Additional
functions
Output
functions
*3
READY indicator Yes (color: green)
READY output Yes (relay: 24 VDC, 0.1 A max.)
Backup indictor Yes (color: red)
Backup output Yes (relay: 24 VDC, 0.1 A max.)
Overcurrent protection Reverse-L dropping, automatic reset, overcurrent detection point:
5.8 to 6.8 A
Overvoltage protection Yes
Parallel operation Yes (Up to 4 Blocks)
Series operation No
Other Ambient operating
temperature
Refer to the derating curve in Engineering Data. (with no condensation
or icing)
Storage temperature -25 to 65°C
Ambient humidity Operating: 25% to 85%; Storage: 25% to 90%
Dielectric strength *4 1.0 kVAC for 1 minute (between all DC connection terminals and PE
terminals; Detection current: 20 mA)
500 VAC for 1 minute (between all DC connection terminals/PE
terminals and all signal output terminals; detection current: 20 mA)
Insulation resistance 100 MΩ min. (between all DC connection terminals and PE terminals)
at 500 VDC
Vibration resistance *5 *6 10 to 55 Hz, 0.375-mm single amplitude for 2 h each in X, Y, and Z
directions
Shock resistance *5 *6 150 m/s2, 3 times each in ±X, ±Y, and ±Z directions
EMI Conducted
Emission *5
Conforms to EN61204-3 EN55011 Class B and based on FCC Class A
Radiated
Emission
Conforms to EN61204-3 EN55011 Class B
EMS Conforms to EN61204-3 High severity levels
Approved
standards
UL: UL508 (Listing; Class 2: Per UL1310) *7, UL60950-1
cUL: CSA C22.2 No.14 (Class 2: Per No. 223) *7
cUR: CSA No. 60950-1
EN/VDE: EN50178 (= VDE0160), EN60950-1 (= VDE0805 Teil 1)
SEMI SEMI F47-0200
Weight 450 g max.
*1. The output characteristics are specified at the power output terminals.
*2. Refer to Backup Time on Catalog for details.
*3. Refer to Functions on Catalog for details.
*4. If the number of S8T-DCBU-02 Buffer Blocks to be connected is “N,” set the detection current to 20 mA × N.
*5. Specified by S8TS-06024[] connection.
*6. Be sure to mount an End Plate (PFP-M: Order separately) on each end of the Buffer Block. Refer to DIN Rails on
       Catalog.
*7. To comply with Class 2, connect one S8TS-06024[] to one S8T-DCBU-02 Buffer Block.

Reference Value

Item Value Definition
Reliability (MTBF) 135,000 hrs min. MTBF stands for Mean Time Between Failures, which is calculated according
to the probability of accidental device failures, and indicates reliability of devices.
Therefore, it does not necessarily represent a life of the product.
Life expectancy 10 yrs. min. The life expectancy indicates average operating hours under the ambient
temperature of 40°C and a load rate of 50%.
Normally this is determined by the life expectancy of the built-in aluminum
electrolytic capacitor.