DL28 is a communications processor that handles data communication connections between measuring and control devices in a heating substation and their integration into remote monitoring and control systems (SCADA) by using diverse transfer routes. DL28 can be connected to SCADA programs in several ways: via local area networks (LAN), wireless computer networks (WLAN), CATV modems, GSM/GPRS/3G routers, as well as via other standard and wireless modems. An established communication link allows for real-time remote monitoring and read-outs of process variables at the heating substation, as well as of alarm conditions.
The DL28 has a plastic enclosure for mounting with a 35mm DIN mounting rail. The front panel features power supply connectors, connectors for USB peripherals, memory cards, Ethernet and serial communication, as well as LED indicators. The communications processor supports microSD memory cards via a push-push connector.

Pin | Signal name | Signal Description |
1 | + | Positive terminal |
2 | GND | Ground terminal |
3 | - | Negative terminal |
PROCESSOR BOARD | |
Central processor | 32-Bit MCU Core ARM926EJ, 454MHz |
Operating system | Linux 2.6.35 |
Memory | 256MB DDR2 SDRAM |
Disc | 4GB Flash |
Ethernet | 1 x USB2.0 Hi-Speed Host, 1 x OTG |
Memory card | microSD, push-push connector |
Real Time Clock (RTC) | Implemented (powered by a CR1220 battery) |
COMMUNICATION BOARD | |
USB | 1 x USB2.0 device, galvanically isolated, FT232R |
Serial ports | Galvanically isolated with send and receive LED indicatorsn S1 – RS-232C (TD, RD, DTR, RTS, CTS, RI, DCD signals) S2 – RS-232C (TD, RD, RTS, CTS signals) or RS-485 (A+ & B-) S3 – RS-232C (TD, RD, RTS, CTS signals) or RS-485 (A+ & B-) |
M-Bus BOARD | |
Serial ports | Galvanically isolated with send and receive LED indicators S4 – M-Bus Master, up to 20 Slave devices S5 – M-Bus Slave S6 – RS-232C (TD, RD, RTS, CTS signals) or RS-485 (A+& B-) |
COMMON CHARACTERISTICS | |
Power supply | 18-36V DC |
Power consumption | 5W |
Enclosure protection | IP40 |
Temperature range | from -20°C to +55°C and from 0 to 95% RH (without condensation) |
Dimensions | 70 x 85 (91) x 73mm |
Mounting | DIN rail 35 mm |
*Minimum functionality kit needs to include the device and an appropriate power supply. Please note that all accessories are sold separately.
Model | SKU | Description | Price | |
PS-2415-DIN | 23601 | Power supply, DIN rail mount, DC24V 15W, AC85-264V 50/60Hz | €11 | €11.00 |
CB-DL28-K1 | 23128 | Serial Cable Assembly 0.3m, RJ45 Male - DB9 Male, for connecting S1 to GSM Terminal GT900 | €4 | €4.00 |
CB-USBAB-2M | 21745 | USB Cable Type A/B 1.8~2m, for connecting to PC for debugging | €4 | €4.00 |
CB-ETH-0.5M | 22133 | Ethernet patch cable, RJ45 Male – RJ45 Male | €1 | €1.00 |