CM520-57 Series — Five-port industrial Wi-Fi gateway
Source filename 2025 revised edition | file date code 260522 · Technical review edition · PDF
CAIMORECM520-57FS
Five-port industrial cellular router
A five-port 5G industrial router with one configurable WAN port and four LAN ports. A serial connection and wide DC supply support integration with industrial equipment.
- Ethernet
- 5 × 10/100 Mbps Ethernet ports
- Serial interface
- 1 × RS232; RS485 available as an ordering option
- DC input
- 6–32 V DC
- Operating temperature
- −35 to +75 °C
Product photography. Open full image ↗
Technical specifications
Options vary by model, hardware revision and firmware.
Key specifications
| Ethernet | 5 × 10/100 Mbps Ethernet ports |
|---|---|
| Serial interface | 1 × RS232; RS485 available as an ordering option |
| DC input | 6–32 V DC |
| Operating temperature | −35 to +75 °C |
Model selection
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source p. 1
| CM520-57F | Cellular: 4G; Wi-Fi: 2.4 GHz; Modems: 1; SIM slots: 1; RS232: Yes; RS485: Optional |
|---|---|
| CM520-57FB | Cellular: 4G; Wi-Fi: 2.4 GHz; Modems: 1; SIM slots: 2; RS232: Yes; RS485: Optional |
| CM520-57FS-GC | Cellular: 5G; Wi-Fi: 2.4 GHz; Modems: 1; SIM slots: 1; RS232: Yes; RS485: Optional |
| CM520-57FBS-GC | Cellular: 5G; Wi-Fi: 2.4 GHz; Modems: 1; SIM slots: 2; RS232: Yes; RS485: Optional |
Industrial platform and protection
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source p. 3
| Processor | Industrial 32-bit processor, 650 MHz; 32 KB D-cache and 64 KB I-cache. The overview identifies MIPS. |
|---|---|
| Wireless / PCB | Industrial wireless module; PCB design following the stated 3H and 3W principles; selected industrial components. |
| Ethernet protection | 1.5 kV electromagnetic isolation. |
| Enclosure | Metal, shielding, enclosure/system isolation, lightning protection and IP31. |
| Power protection | 7-32 V DC in design section; later power table says 7-36 V DC. Reverse-polarity, overvoltage and overcurrent protection. |
| SIM / serial protection | 1.8/3/5 V push-type SIM/UIM; 15 kV ESD protection. RS232 also described with 15 kV ESD protection. |
| Memory | MMU; Flash 128 Mbit, expandable to 256 Mbit; SDRAM 1 Gbit. Packet buffering and complete TCP/IP stack described. |
External interfaces
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 4, 7
| Ethernet | 1 RJ45 WAN and 4 RJ45 LAN ports, 10/100 Mbps; WAN switchable to LAN; 1.5 kV isolation. |
|---|---|
| WAN / LAN | 1 WAN, configurable as LAN; 4 LAN ports. |
| Terminal serial port | 1 RS232 port, optionally configured as RS485 (specify when ordering). Data bits: 7/8; stop bits: 1/2; parity: none/odd/even; 300-4000000 bit/s; no, hardware or software flow control. Other feature text suggests both ports: Confirmation required. |
| Cellular / Wi-Fi antennas | SMA female, 50 ohm. Source lists cellular extensions 3 m / 5 m / 10 m / 15 with the final unit omitted; confirm the last length. |
| SIM/UIM | 1.8/3/5 V push-type full-size card interface, 15 kV ESD protection; slot count depends on model. |
| Power | 3-pin terminal socket. |
| Indicators | POWER, ONLINE and WIFI. |
| RESET | Restore factory defaults. |
Network connectivity and IP functions
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 5-7
| Network access | APN / VPDN |
|---|---|
| Authentication | CHAP / PAP / MS-CHAP / MS-CHAPv2 |
| Radio system | See cellular radio specifications. |
| LAN protocols | ARP / Ethernet |
| IP applications | Ping, traceroute, DHCP server/relay/client, DNS relay, DDNS, Telnet, SSH, HTTPS, TFTP, FTP and SFTP. |
| Routing | Static and dynamic routes. |
Security and reliability
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 5-7
| Firewall | Stateful packet inspection (SPI), denial-of-service (DoS) protection, multicast/Ping filtering and access-control lists (ACL). |
|---|---|
| Address translation | NAT, PAT, DMZ, port mapping and virtual servers. |
| Users / AAA | User privilege levels; local authentication, RADIUS, TACACS+ and LDAP. |
| Data security | CA support, including automatic application; SM1/SM2/SM3/SM4 algorithms. |
| Backup | VRRP, interface backup and optional dual-SIM backup; depends on ordered model. |
| Link monitoring | Heartbeat checks and automatic reconnection. |
| Watchdog | Operating self-check and fault self-recovery. |
Management and optional integration
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 5-7
| WLAN | Marked optional in the software-table heading; confirm ordered configuration. |
|---|---|
| Configuration | Local or remote HTTPS, Telnet and SSH. |
| "Upgrade method" source row | The source actually lists local/remote log output and log retention after power loss. Heading/content mismatch: Confirmation required. |
| SMS, optional | Status inquiry, configuration and restart. |
| On-demand dialing | Data-triggered or SMS-triggered connection; scheduled online/offline operation. |
| Management | SNMP and power-industry TR-069; DM central management and batch configuration. |
| Development / platforms, optional | Python custom development; AWS, Tencent Cloud, power-industry platforms, Alibaba Cloud; central and batch management. |
| Industrial protocols, optional | Modbus TCP, Modbus RTU, EtherNet/IP and Modbus TCP Slave. |
Additional software-table entries
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 5-7
| Optional WLAN | IEEE 802.11ac/a/b/g/n; open-system/shared-key/WPA/WPA2 authentication; WEP/TKIP/AES encryption. Detailed Wi-Fi table lists only b/g/n: Confirmation required. |
|---|---|
| WLAN modes | AP and Client; detailed table also lists repeater. |
| DM / diagnostics | Centralized management and batch configuration; Ping, traceroute and Sniffer packet capture. |
Security and reliability additions
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 5-7
| Data security | CA support, including automatic application ; SM1/SM2/SM3/SM4 cryptographic algorithms. |
|---|---|
| VPN | IPsec, L2TP, PPTP, GRE, N2N, L2TP over IPsec, GRE over IPsec, EOIP and OpenVPN. |
| Hardware encryption | State Grid, China Southern Power Grid and Chinese commercial-cryptography encryption support, . Exact algorithms, modules and approvals require confirmation. |
| Link health | Online maintenance, heartbeat detection and automatic reconnection. |
| Management | SNMP and power-industry TR-069; DM central management and batch configuration. |
| DHCP / translation | DHCP server/client; SNAT/DNAT port mapping; DMZ. |
Communication, Wi-Fi and access functions
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 5-7
| Transport | 5G/4G/3G; Ethernet-to-cellular; Ethernet-to-Wi-Fi; serial/RS485-to-cellular, Wi-Fi and Ethernet. |
|---|---|
| Transparent services | DTU and MQTT transparent transfer; APN/VPDN; VXLAN. |
| Link backup | Wired/cellular mutual backup; Wi-Fi/cellular primary/backup. |
| Health checks | Online maintenance and DTU LAN-client heartbeat packets. |
| Radio restrictions | Cellular frequency locking and SIM locking, as named in source. |
| Wi-Fi access | Client-count limits and client isolation. |
| Multiple SSIDs | Up to four Wi-Fi names, each with an independent MAC address. |
| Identity / controls | MAC and serial-number persistence; access restrictions; port alarms. |
| Positioning | BeiDou-only, GPS-only or combined positioning is listed in the software section; no positioning interface is specified in the physical table. Confirm ordered hardware. |
Optional customized and platform functions
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 5-7
| Three-link backup | Wired, Wi-Fi and cellular links as mutual primary/backup. |
|---|---|
| IP traffic splitting | Distribute flows by source/destination IP across network links, servers or paths to reduce congestion and improve utilization/stability. |
| Wi-Fi diagnostics | Client signal-strength monitoring. |
| Session records | Online/offline timestamps for wired, cellular and Wi-Fi users. |
| TF security | Software encryption for TF cards. Physical TF-slot availability depends on hardware. |
| Product customization | Customer-customized product log and model identifier, as written; whether log means logo Confirmation required. |
| Central platform | Remote parameters, OTA, remote multimedia updates (music/video/advertising), allow/block lists, traffic and online statistics, radio-system statistics, SMS/WeChat/Wi-Fi authentication, traffic and speed controls, time limits, Internet-behavior controls, Wi-Fi probe and multi-level user management. Backend/platform scope requires configuration review. |
Optional development and industrial protocols
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 5-7
| Development / clouds | Python custom development; Amazon AWS, Alibaba Cloud, Tencent Cloud and power-industry platforms. |
|---|---|
| Industrial protocols | Modbus TCP; Modbus TCP/RTU conversion; Modbus RTU; EtherNet/IP; Modbus TCP Slave; MQTT; Ntrip Client and Ntrip Server. |
| Power-industry protocols | 101/104, 61850 and TR-069, as written; no unspecified editions or conformity inferred. |
| Environmental protocol | HJ212-2005/2017. |
Cellular parameters
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 8-9
| Wireless module | Industrial-grade module. |
|---|---|
| 5G SA/NSA bands | n1/n2/n3/n5/n7/n8/n20/n28/n41/n66/n71/n77/n78/n79 |
| TDD frequency group | LTE TDD: 2600/2300 MHz; UMTS: 2100/900 MHz; GSM: 850/900/1800/1900 MHz; UMTS Rx diversity: 2100/900 MHz. |
| FDD frequency group | LTE FDD: 2600/2100/1800/DD800 MHz (DD800 reproduced as printed); UMTS and UMTS Rx diversity: 2100/900 MHz. |
| Radio schemes | NR/LTE/UMTS/HSPA+/HSDPA/HSUPA/WCDMA/EDGE/GSM |
| 5G NR rate | DL 3.4 Gbps / UL 350 Mbps. Modem theoretical figures, not Ethernet throughput. |
| TDD rates | LTE TDD: DL 68 Mbps / UL 17 Mbps; DC-HSPA+: DL 42 Mb/s (Category 24); HSPA+: DL 28 Mb/s (Category 18); HSDPA: DL 14.4 Mb/s (Category 8); HSUPA+: DL 5.76 Mb/s (Category 6), as printed; WCDMA CS: UL/DL 64 kbps; WCDMA PS: UL/DL 384 kbps. |
| FDD rates | LTE FDD: DL 100 Mbps / UL 50 Mbps; other DC-HSPA+, HSPA+, HSDPA, HSUPA+ and WCDMA values are the same as the TDD table. |
| Transmit power | LTE: 23 dBm; WCDMA/HSDPA: 24 dBm. |
| Receiver sensitivity | <-109 dBm |
| module functions | Data, voice, SMS and fax; actual hardware/firmware applicability Confirmation required. |
| Power private network | 1.8 GHz power-industry private-network bands and integrated public/private modules. |
| Overseas options | The source claims broad international coverage; specify country and required bands so an appropriate optional modem can be selected. No universal band or certification claim is inferred. |
Wi-Fi
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 8-9
| Module | Integrated chipset Wi-Fi module. |
|---|---|
| Standards / rates | 802.11 b/g/n; 6/9/12/18/24/36/48/54 Mbps; maximum stated 300 Mbps. |
| Encryption | WEP, WPA and WPA2; hardware security engines listed as 802.11i 4.0, TKIP, AES and CCMP. |
| Modes | AP and repeater. |
| Coverage claim | Up to 100 m outdoors without obstructions; test conditions not specified. Confirmation required. |
Hardware
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 9-10
| CPU | 650 MHz industrial embedded processor with MMU. |
|---|---|
| Flash | 128 Mbit, expandable; reliability section states up to 256 Mbit. |
| SDRAM | 1 Gbit, described as expandable. |
Power and environment
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 9-10
| Input | 7-36 V DC in power table; design section gives 7-32 V. Reverse-polarity, overvoltage and overcurrent protection. Confirmation required. |
|---|---|
| Standard supply | 9 V DC / 1.33 A |
| Communication current | Average 430 mA at +9 V DC; registration peak 1.0 A at +9 V DC. |
| Standby | Average <200 mA at +9 V DC. |
| Operating temperature | -35 to +75 °C |
| Storage | -40 to +85 °C |
| Relative humidity | 95%, non-condensing. |
EMC parameters
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 9-10
Certification scope and test conditions depend on the selected model. Request the applicable documentation.
| ESD | EN 61000-4-2, level 3 |
|---|---|
| Radiated electric field | EN 61000-4-3, level 3 |
| Electrical fast transient | EN 61000-4-4, level 3 |
| Surge | EN 61000-4-5, level 3 |
| Conducted disturbances | EN 61000-4-6, level 3 |
| Power-frequency magnetic field | EN 61000-4-8; horizontal/vertical 400 A/m (level 3), . Confirmation required. |
Physical characteristics
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 9-10
| Enclosure | Metal, shielding, isolated enclosure/system and lightning protection; IP31. |
|---|---|
| Body | 125 x 103.2 x 38 mm; excludes antennas and mounting hardware; tolerance +/-0.5 mm. |
| Package | 350 x 215 x 88 mm |
| Weight | 0.44 kg |
| Shock / vibration / drop | IEC 60068-2-27 / IEC 60068-2-6 / IEC 60068-2-32 |
certifications
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source pp. 9-10
Certification scope and test conditions depend on the selected model. Request the applicable documentation.
| Domestic | MIIT network-access permit, CRCC, Ministry of Housing and Urban-Rural Development interoperability certificate, CCC, radio-committee certificate, EMC and high/low-temperature testing. |
|---|---|
| International | CE, FCC, E-mark, CB and RoHS. |
| Scope | Certificate identifiers, validity and exact model scope Confirmation required. |
Terminal definitions
CM520-57 Series — Five-port industrial Wi-Fi gateway · Source filename 2025 revised edition | file date code 260522 · Source p. 11
| 1 | Label: RXD; Description: RS232 receive |
|---|---|
| 2 | Label: TXD; Description: RS232 transmit |
| 3 | Label: GND; Description: Common ground |
| 4 | Label: IO2; Description: I/O channel 2 |
| 5 | Label: GND; Description: Common ground |
| 6 | Label: 485A; Description: RS485 + |
| 7 | Label: 485B; Description: RS485 - |
| 8 | Label: IO1; Description: I/O channel 1 |
System connectivity
From field equipment to your system.
See how CM520-57FS fits into your installation.
Illustrative connection architecture. External equipment and customer software are shown for context. Interfaces and options vary by configuration.
Downloads
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CM520-57 — Wireless router user manual
Source revision V1.3 | 18 July 2022 · Technical review edition · PDF