RM31E 3:1 Rack/Tower Online UPS 6–10 kVA
RM31E is a compact 3U rack/tower online double-conversion UPS, available in 6 kVA / 6 kW and 10 kVA / 10 kW ratings, for sites with three-phase electrical distribution and protected single-phase critical loads. It supports 3:1 and optional 1:1 operation with DSP digital control, PF 1.0 pure sine-wave output and 0 ms transfer time, with compatible external rack battery cabinets and parallel operation up to four units by configuration.
Engineered for 3:1 Rack/Tower Critical Power
Three-phase input and single-phase output online UPS architecture for sites with three-phase distribution and protected single-phase IT, telecom, security or control loads installed in standard 19-inch racks or tower environments.
3-Phase In / 1-Phase Out
Accepts 380 / 400 / 415 Vac three-phase input and delivers 220 / 230 / 240 Vac single-phase output for critical equipment supplied from a three-phase electrical network. Optional single-phase input and single-phase output operation is also supported by configuration.
3U Rack/Tower Form Factor
Compact 3U rack/tower convertible design for standard 19-inch equipment racks or freestanding tower installation. Suitable for server rooms, telecom racks, control rooms and space-constrained IT environments.
Online Double-Conversion VFI
True online double-conversion architecture with DSP digital control provides regulated pure sine-wave output and 0 ms transfer time between online and battery operation for sensitive single-phase critical loads.
PF 1.0 Output & Low Input Distortion
Output PF 1.0 (kW = kVA) provides full usable kW capacity. Active input power-factor correction delivers input PF ≥0.99 and input THDi ≤3% at linear load, helping reduce upstream current demand and harmonic loading.
Parallel up to 4 Units
Selected RM31E configurations support parallel operation of up to four units for capacity expansion or N+X redundancy, subject to approved parallel accessories, matching UPS ratings and project design.
Flexible Runtime & Monitoring
Compatible external rack battery cabinets extend backup time according to the connected load and required runtime. Communication options include RS-232, RS-485, EPO and optional SNMP or relay-card interfaces by configuration for remote monitoring, dry-contact signalling and integration with network-management, building-management or control-room systems.
Expand Your RM31E System
Optional accessories for runtime extension, remote monitoring, rack installation and maintenance support – selected according to the RM31E model and project configuration.
External Rack Battery Cabinets
Compatible RC-series rack battery cabinets provide extended runtime for RM31E long-runtime configurations. Battery quantity, DC bus voltage, cabinet capacity and charging requirements are selected according to the UPS model, connected load and required backup time.
Rack Rail Kit
Adjustable 19-inch rack rails support secure RM31E installation in compatible server and telecom cabinets. Rail compatibility must be confirmed against the cabinet depth, mounting-post spacing and equipment weight.
SNMP Network Card
Optional intelligent communication card provides remote UPS monitoring, web access, event notifications and supported network-management integration. Compatible SNMP or relay-card options are available by configuration.
External Maintenance Bypass PDU
Provides an external bypass and isolation arrangement so the connected load can remain supplied during UPS service or replacement, subject to correct installation, available bypass power and the prescribed switching procedure. Available by model and rating.
Technical Details
Complete specifications for the RM31E 6–10 kVA series.
| Specification | 6 kVA | 10 kVA |
|---|---|---|
| Full Name | RM31E 3:1 Online Rack / Tower UPS | |
| Topology | Online double-conversion VFI with DSP digital control | |
| Phase | 3:1 / 1:1 operation (3-phase in / 1-phase out; 1-phase in / 1-phase out supported by configuration) | |
| Form Factor | 3U rack / tower convertible | |
| Capacity | 6 kVA / 6 kW | 10 kVA / 10 kW |
| Output Power Factor | PF 1.0 standard | |
| Input Voltage | 380 / 400 / 415 Vac 3Ph+N+PE; 220 / 230 / 240 Vac 1Ph supported by configuration | |
| Display | Segment LCD; optional TFT colour display by configuration | |
| Operating Modes | Online, ECO, bypass, battery and 50 / 60 Hz frequency-converter modes; generator-fed and cold-start operation supported | |
| Parallel | Up to 4 units by configuration | |
| Standards | CE, IEC / EN 62040-1, IEC / EN 62477-1, IEC / EN 62040-2 (EMC), LVD (by series) | |
| Specification | 6 kVA | 10 kVA |
|---|---|---|
| Input Voltage | 380 / 400 / 415 Vac 3Ph+N+PE; 220 / 230 / 240 Vac 1Ph supported by configuration | |
| Input Range | 208–478 Vac (3-phase input); 120–270 Vac (1-phase input) | |
| Input Frequency | 40–70 Hz; 50 / 60 Hz auto-sensing | |
| Input Power Factor | ≥0.99 (active PFC) | |
| Input THDi | ≤3% at linear load | |
| Output Voltage | 220 / 230 / 240 Vac L+N+PE, ±1% | |
| Output Power Factor | PF 1.0 standard (kW = kVA) | |
| Output THDv | ≤2% linear load; ≤5% non-linear load | |
| Output Frequency (battery) | 50 / 60 Hz ±0.1% | |
| Transfer Time | 0 ms (AC→Battery); 0 ms (Inverter→Bypass) | |
| Crest Factor | 3:1 | |
| Online Efficiency (VFI) | Up to 93.5% | Up to 93.5% |
| ECO Mode Efficiency | ECO mode available; efficiency subject to confirmed model specification | |
| Specification | Details |
|---|---|
| Battery Type | 12 V sealed VRLA batteries, 7 Ah or 9 Ah by cabinet configuration |
| Battery Configuration | 16 / 18 / 20 pcs configurable |
| Standard DC Bus | ±96 / ±108 / ±120 Vdc |
| Long-Run DC Bus | ±192 / ±204 / ±216 / ±228 / ±240 Vdc, 32–40 pcs supportable |
| Charger Current | 6 kVA: up to 12 A; 10 kVA: up to 14 A |
| External Battery Cabinets | RC20120N: 1 × 20 batteries; RC40120N: 2 × 20 batteries |
| Derating Note | 20 pcs: no output derating; 18 pcs: PF 0.9; 16 pcs: PF 0.8 |
| Battery Runtime | Calculated according to connected load, battery quantity and capacity, ambient temperature, battery condition and required backup time |
| Specification | 6 kVA | 10 kVA |
|---|---|---|
| UPS Dimensions (W×D×H) | 443 × 580 × 131 mm | |
| Rack Height | 3U | |
| Net Weight | 27 kg | 28 kg |
| Installation | Rack / tower convertible | |
| Rack Rails | Optional 19-inch rack rail kit; cabinet compatibility subject to rail and mounting dimensions | |
| Battery Cabinet RC20120N | 443 × 720 × 131 mm (3U) · 58 kg (7 Ah) / 63 kg (9 Ah) | |
| Battery Cabinet RC40120N | 482 × 861.5 × 175 mm (4U) · 138 kg (7 Ah) / 154 kg (9 Ah) | |
| Colour | Black | |
| Interface | Details |
|---|---|
| Standard Communication | RS-232, RS-485, EPO and auxiliary maintenance / control interfaces by configuration |
| Optional Network Card | SNMP network card (by configuration) |
| Optional Relay Card | Relay / dry-contact card by configuration |
| Monitoring Integration | Network-management, building-management or control-room, by configuration |
| Maintenance Bypass | Optional external maintenance bypass PDU |
| Display | Segment LCD; optional TFT colour display by configuration |
| Parallel | Approved parallel kit for up to four matching RM31E units, subject to configuration and commissioning requirements |
AC Mode Overload
| Load Level | Duration | Action |
|---|---|---|
| 100–110% | 60 minutes | Transfer to bypass after the stated duration |
| 110–125% | 10 minutes | Transfer to bypass after the stated duration |
| 125–150% | 1 minute | Transfer to bypass after the stated duration |
| >150% | Immediate | Immediate transfer to bypass |
Transfer to bypass requires bypass power to be available and within tolerance; otherwise the UPS may shut down.
Battery Mode Overload
| Load Level | Duration | Action |
|---|---|---|
| 100–110% | 10 minutes | UPS shutdown after the stated duration |
| 110–125% | 1 minute | UPS shutdown after the stated duration |
| 125–150% | 5 seconds | UPS shutdown after the stated duration |
| >150% | Immediate | Immediate UPS shutdown |
Bypass mode: below 125%, long-term operation, subject to bypass protection and operating limits.
Protections & Alarms
| Protection | Description |
|---|---|
| Output | Overload, short-circuit and output low-voltage protection |
| Battery | Battery overcharge and overdischarge protection |
| Thermal | Overtemperature protection |
| Cooling System | Fan-fault alarm |
| Emergency Control | EPO interface |
| Alarms & Indication | Audible alarm and LCD status indication by display configuration |
| Parameter | Specification |
|---|---|
| Operating Temperature | 0–40 °C |
| Storage Temperature | −25 to +55 °C |
| Relative Humidity | 0–95% non-condensing |
| Altitude | <1500 m without derating; derating required above 1500 m |
| Noise | <53 dB at 1 m (6 kVA); <55 dB at 1 m (10 kVA) |
| Cooling | Forced-air cooling with intelligent fan-speed regulation |
| Safety | IEC / EN 62040-1, IEC / EN 62477-1 |
| EMC | IEC / EN 62040-2 |
| Certifications | CE, EMC, LVD (by series) |
Ideal For
RM31E is designed for 19-inch rack or tower installations where a three-phase utility or generator source must supply protected 220 / 230 / 240 Vac single-phase critical loads at 6 or 10 kVA.
Server Rooms
3:1 online UPS protection for server racks, switches, storage systems, firewalls and IT equipment requiring single-phase output from a three-phase building supply.
Telecom Cabinets
Compact 3U rack/tower UPS protection for telecom switching, routing, transmission and access-network equipment supplied from three-phase utility or generator power.
Edge Computing
Online UPS protection for distributed IT nodes and edge deployments requiring three-phase input, protected single-phase output and flexible runtime.
Network Closets
Rack/tower UPS protection for switches, routers, firewalls and structured-network equipment in buildings with three-phase distribution and single-phase IT loads.
Security Systems
3:1 UPS backup for NVRs, access-control servers, alarm panels, monitoring workstations and security-network equipment supplied from a three-phase electrical network.
Commercial & Financial IT
Online UPS protection for branch IT rooms, payment systems, network racks, security servers and critical workstations in commercial buildings with three-phase distribution.
Need Single-Phase Input, PF 1.0 Rack Power or Full 3:3 Output?
Compare RM31E with related ATENCO online UPS platforms for standard single-phase rack applications, higher usable kW in PF 1.0 rack/tower format, or full three-phase input and output systems.
Online Single-Phase Rack/Tower UPS 1–10 kVA
- Single-phase input / single-phase output
- Online double-conversion, pure sine-wave
- Output power factor up to 0.9 by model
- Rack/tower convertible design by model
- Internal / long-runtime by model
PF 1.0 Rack/Tower UPS 6–10 kVA
- Single-phase input / single-phase output
- Three-level inverter technology
- Output PF 1.0 kW/kVA
- 2U / 4U rack/tower by model
- Dual intelligent slots by model
3:3 Online Rack/Tower UPS 10–50 kVA
- Three-phase input / three-phase output
- Online double-conversion VFI with DSP control
- Output PF 1.0 kW/kVA
- Rack/tower chassis by capacity
- Parallel up to 4 units, N+X by config
RM31E 3:1 Rack / Tower UPS FAQ
Answers about RM31E three-phase input and single-phase output architecture, 6 and 10 kVA ratings, PF 1.0 output, external battery runtime, parallel operation and communication options.
What does RM31E mean?
What is the difference between RM31E and TM31E?
What is the difference between RM31E and RM33E?
What capacities are available for RM31E?
Can RM31E be paralleled for redundancy?
What monitoring options does RM31E support?
What battery runtime options are available for RM31E?
Can RM31E operate with single-phase input?
Can RM31E operate from a generator?
Does RM31E support a maintenance bypass?
Which applications are not suitable for RM31E?
Size Your RM31E 3:1 UPS Project
Share your connected load, required backup time, redundancy plan, three-phase input voltage, installation format, generator details and communication requirements. ATENCO will recommend the suitable 6 or 10 kVA RM31E configuration, external battery system, parallel arrangement, rack installation accessories and compatible monitoring options for your project.
Send Project Requirements
Provide the connected load in kW and kVA, load type and peak current, required runtime, site input voltage, rack or tower installation, generator details where applicable, redundancy requirement and communication preferences.
Receive UPS Selection & Sizing
ATENCO will recommend the suitable RM31E rating and configuration, battery-rack arrangement, charger setting, parallel design, installation accessories and compatible communication options.