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- Part number
- 6EP1931-2FC21
- Model no
- DC UPS
Siemens has announced the end of 6EP1931-2FC21
Once production ends, supply depends on remaining stock.
No replacement announced yet. Tell us the application and we will propose an alternative.
- CE
- EAC
Siemens 6EP1931-2FC21 SITOP DC UPS 24V/40A No Interface DC UPS Module
SITOP DC UPS module, 24V DC / 40A output, no interface, 97.2% efficiency, IP20.
Description
About the DC UPS
About the DC UPS
The Siemens 6EP1931-2FC21 is a SITOP DC UPS module rated 24 V DC / 40 A output, drawing 22...29 V DC / 43 A at the input, that bridges mains power cuts with a connected battery module. It has no PC interface and relies on LED status indicators and floating relay contacts, reaching 97.2% efficiency at rated output.
Certifications & Standards
- CE
- cULus
- EAC
- ABS
- DNV
- EPD
Selection Notes
This is the 40 A member of the SITOP DC UPS family without a PC interface, sized for the wider enclosure (102 mm vs 50 mm) that the higher current demands. Choose the USB-interface 40 A variant instead when a PC needs to log battery status or set the buffer voltage, or the 6 A or 15 A variants in the same family for smaller loads. At 40 A the module draws 43 A at the input and dissipates 28.6 W at rated output, so enclosure ventilation and adjacent-module spacing matter more than on the smaller variants.
Applications
Bridges the 24 V DC control supply for PLCs, remote I/O, and HMI panels through short mains interruptions until standby generators start or the supply recovers, using a separately ordered battery module for energy storage.
Specification
Full specification
General information 3
| product brand name | SITOP |
|---|---|
| product type designation | DC UPS |
| type of current supply | DC UPS 24 V/40 A |
Input 6
| voltage curve at input | DC |
|---|---|
| supply voltage at DC rated value | 24 V |
| input voltage at DC | 22 ... 29 V |
| adjustable response value voltage for buffer connection preset | 22.5 V |
| adjustable response value voltage for buffer connection | 22 ... 25.5 V; Adjustable in 0.5 V increments |
| input current at rated input voltage 24 V rated value | 40 A; + approx. 2.6 A with empty battery |
Memory 3
| type of energy storage | with batteries |
|---|---|
| product function DC-UPS modularly expandable | Yes |
| design of the mains power cut bridging-connection | Dependent on connected battery and load current, see selection table battery module and mains buffering times as well as the relevant important information notes! |
Show all 90 specifications ↓ Show less ↑78 more values in Identification, Output, Efficiency, Protection and monitoring, Interfaces, Safety, Standards, specifications, approvals, Standards, specifications, approvals marine classification, Standards, specifications, approvals Environmental Product Declaration, Ambient conditions, Connection method, Mechanical data, Accessories, Additional information, Logistics.
Identification 10
| Part number | 6EP1931-2FC21 |
|---|---|
| Type designation | DC UPS |
| Brand | Siemens |
| Condition | New, factory sealed |
| Source | Siemens and its authorised distributors |
| Warranty | Manufacturer warranty |
| Lifecycle status | Phase-out announced by the manufacturer |
| EAN | 4025515151227 |
| ETIM class | EC000382 |
| eCl@ss | 27040705 |
Output 11
| output voltage: in normal operation at DC rated value | 24 V |
|---|---|
| output voltage: in buffering mode at DC rated value | 24 V |
| formula for output voltage | Vin - approx. 0.5 V |
| startup delay time typical | 1 s |
| voltage increase time of the output voltage typical | 360 ms |
| output voltage in buffering mode at DC | 19 ... 28.5 V |
| output current: rated value | 40 A |
| output current: in normal operation | 0 ... 40 A |
| output current: in buffering mode | 0 ... 40 A |
| peak current | 42 A |
| charging current | 1 A, 2 A |
Efficiency 5
| efficiency in percent: at rated output voltage for rated value of the output current typical | 97.2 % |
|---|---|
| efficiency in percent: in case of operation on rechargeable battery typical | 96.9 % |
| power loss [W]: at rated output voltage for rated value of the output current typical | 28.6 W |
| power loss [W]: in case of operation on rechargeable battery typical | 33.6 W |
| supplied active power typical | 960 W |
Protection and monitoring 4
| product function: reverse polarity protection against energy storage unit polarity reversal | Yes |
|---|---|
| product function: reverse polarity protection against input voltage polarity reversal | Yes |
| display version: for normal operation | Normal operation: LED green (OK), floating changeover contact "Bat/OK" to setting "OK" ("OK" means: Voltage of the supplying power supply unit is greater than cut-in threshold set at the DC UPS module); Lack of buffer standby: LED red (alarm), floating changeover contact "Alarm/Bat" to setting "Alarm"; Battery replacement required: LED red (alarm) flashing with approx. 0.25 Hz, floating changeover contact "Alarm/Bat" switching with approx. 0.25 Hz; Energy storage > 85%: LED green (Bat > 85%), floating NOcontact "Bat > 85" closed; Permissible contact current capacity: DC 60 V/1 A or AC 30 V /1 A |
| display version: in buffering mode | Buffered mode: LED yellow (Bat), floating changeover contact "OK/Bat" to setting "Bat"; Prewarning battery voltage 85%: LED green (Bat > 85%), floating NO contact "Bat > 85" closed |
Interfaces 3
| product component PC interface | No |
|---|---|
| product function communication function | No |
| design of the interface | without |
Safety 5
| galvanic isolation between input and output | No |
|---|---|
| operating resource protection class | Class III |
| protection class IP | IP20 |
| standard: for emitted interference | EN 55022 Class B |
| standard: for interference immunity | EN 61000-6-2 |
Standards, specifications, approvals 4
| certificate of suitability: CE marking | Yes |
|---|---|
| certificate of suitability: UL approval | Yes; cULus-Listed (UL 508, CSA C22.2 No. 107.1), File E197259 |
| certificate of suitability: EAC approval | Yes |
| MTBF at 40 °C | 522 739 h |
Standards, specifications, approvals marine classification 3
| shipbuilding approval | Yes |
|---|---|
| Marine classification association: American Bureau of Shipping Europe Ltd. (ABS) | Yes |
| Marine classification association: Det Norske Veritas (DNV) | Yes |
Standards, specifications, approvals Environmental Product Declaration 5
| Environmental Product Declaration | Yes |
|---|---|
| global warming potential [CO2 eq]: total | 898.2 kg |
| global warming potential [CO2 eq]: during manufacturing | 45.1 kg |
| global warming potential [CO2 eq]: during operation | 851.9 kg |
| global warming potential [CO2 eq]: after end of life | 0.84 kg |
Ambient conditions 4
| ambient temperature: during operation | -25 ... +60 °C; with natural convection |
|---|---|
| ambient temperature: during transport | -40 ... +85 °C |
| ambient temperature: during storage | -40 ... +85 °C |
| environmental category according to IEC 60721 | Climate class 3K3, 5 ... 95% no condensation |
Connection method 5
| type of electrical connection | screw terminal |
|---|---|
| at input | 24 V DC: 2 screw terminals for 0.33 ... 10 mm2/22 ... 7 AWG |
| at output | 24 V DC: 2 screw terminals for 0.33 ... 10 mm2/22 ... 7 AWG |
| for rechargeable battery module | 24 V DC: 2 screw terminals for 0.33 ... 10 mm2/22 ... 7 AWG |
| for control circuit and status message | 10 screw terminals for 0.5 ... 2.5 mm2/20 ... 13 AWG |
Mechanical data 11
| width × height × depth of the enclosure | 102 × 125 × 125 mm |
|---|---|
| installation width × mounting height | 102 mm × 225 mm |
| required spacing: top | 50 mm |
| required spacing: bottom | 50 mm |
| required spacing: left | 0 mm |
| required spacing: right | 0 mm |
| fastening method | Snaps onto DIN rail EN 60715 35x7.5/15 |
| DIN-rail mounting | Yes |
| S7 rail mounting | No |
| wall mounting | No |
| housing can be lined up | Yes |
Accessories 1
| electrical accessories | Battery module |
|---|
Additional information 1
| other information | Specifications at rated input voltage and ambient temperature +25 °C (unless otherwise specified) |
|---|
Logistics 6
| Net weight | 1 kg |
|---|---|
| Country of origin | Romania |
| Shipping weight | 1.5 kg |
| Ships from | Türkiye |
| Dispatch | — |
| Stock | On request |
Source: manufacturer data · Last verified: 01 Nov 2026
Documents
Documents for 6EP1931-2FC21
No documents are on file for this part yet.
Ask us for the datasheet
Certifications
Certifications and standards
- CE
- EAC
- CE marking
- EAC approval
- shipbuilding approval
- American Bureau of Shipping Europe Ltd. (ABS)
- Det Norske Veritas (DNV)
- Environmental Product Declaration
Quick answers
Questions about the DC UPS
What is the rated current of DC UPS?
The rated current of DC UPS is 40 A.
Which supply voltage is DC UPS rated for?
The rated operational voltage of DC UPS is 24 V AC.
What motor power is DC UPS rated for?
The rated motor power of DC UPS is 97.2 % kW.
What is the HS code of DC UPS for customs?
The tariff (HS) code on file for DC UPS is 85044060.
What is the EAN of DC UPS?
The EAN (GTIN) of DC UPS is 4025515151227.
Where does DC UPS ship from, and how fast?
DC UPS ships from Türkiye. Shipping calculated at checkout · import duties and taxes paid on arrival.
Guides
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Reviews
Customer reviews
Series
Siemens SITOP DC
- Brand
- Siemens
- Series
- SITOP DC
