Data Acquisition


  • Built-in Web Server
  • Web HMI
  • Support for both Modbus TCP and Modbus UDP Protocols
  • Communication Security
  • 2-port Ethernet Switch for Daisy-Chain Topology
  • Dual Watchdog
  • I/O Pair Connection
  • Built-in I/O
    • AI: 8 Channels True RMS Input
    •  DO: 4 Channels


The ET-7217RMS is an 8-channel differential AC input and 4-channel digital outputs module that is used to convert the AC input signals to their True RMS DC values. The RMS input range can be from +150 mVrms to +10 Vrms, and each channel can be configured individually. The ET-7217RMS is a complete, high-accuracy, RMS-to-DC converter that computes the True RMS DC value of any complex waveform. It also features 4 kV ESD protection, 2500 VDC intra-module isolation, and ±35 Vrms/±28 VDC overvoltage protection.


 Built-in Web Server Yes


 CPU Module
 Watchdog Timer Module, Communication (Programmable)


 2-way Isolation Ethernet: 1500 VDC
I/O: 2500 VDC


 EMS Protection
 EFT (IEC 61000-4-4) ±2 kV for Power Line
 ESD (IEC 61000-4-2) ±4 kV Contact for Each Terminal
±8 kV Air for Random Point
 Surge (IEC 61000-4-5) ±2 kV for Power Line


 LED Indicators
 Status Run, Ethernet, I/O


 Analog Input
 Channels 8 (Differential)
 Type True RMS
 Resolution 16-bit
 Accuracy Sinusoid:
50/60 Hz: ±0.15% of FSR
45 Hz to 10 kHz: ±0.5% of FSR

Crest Factor = 1 to 2: ±0.2% of FSR
Crest Factor = 2 to 3: ±0.35% of FSR

0 to 10 Vrms / 0 to 5 Vrms / 0 to 1 Vrms: ±0.3% of FSR
0 to 500 mVrms / 0 to 150 mVrms: ±0.7% of FSR
 Sampling Rate 10 Hz (total channels)
 Input Impedance >2 MΩ
 Overvoltage Protection ±35 Vrms/±28 VDC
 Individual Channel Configuration Yes


 Digital Output
 Channels 4
 Type Isolated Open Collector
 Sink/Source (NPN/PNP) Sink
 Load Voltage +5 to +50 VDC
 Load Current 700 mA/channel
 Overvoltage Protection +60 VDC
 Overload Protection 1.4 A
 Short-circuit Protection Yes
 Power on Value Programmable
 Safe Value Programmable


 Ports 2 x RJ-45, 10/100 Base-TX, Swtich Ports
 LAN bypass Yes
 Security ID, Password and IP Filter
 Protocol Modbus TCP, Modbus UDP


 Reverse Polarity Protection Yes
 Consumption 4.2 W (max.)
 Powered from Terminal Block +12 to +48 VDC


 Dimensions (mm) 72 x 123 x 35 (W x L x H)
 Installation DIN-Rail mounting


 Operating Temperature -25 ~ +75 °C
 Storage Temperature -30 ~ +80 °C
 Humidity 10 to 90% RH, Non-condensing



ET-7217RMS     CR  Ethernet I/O Module with 2-port Ethernet Switch, with 8-ch AI, 4-ch DO (RoHS) 1