RTCU NX-900 Technical Manual V1.02
Advanced M2M/IIoT Gateway
Logic IO ApS.
Ph: (+45) 7625 0210
Holmboes Allé 14
Fax: (+45) 7625 0211
8700 Horsens
Page 18 of 45
Denmark
Digital I/O
The RTCU NX-910 has five digital inputs and four normally-open relay outputs.
The outputs are high performance relays with good current handling capabilities.
Digital input 1-4 have multiple operating modes. Please refer to the digital input section for
additional information.
Relay outputs
The digital outputs control four relays and they act like normally-open contacts, where one side
must be connected to a source that needs switching and the other contact terminal is the output.
The source can be either VAC or VDC but the maximum switchable voltage and current must not
be exceeded. Please refer to specification page.
There are no internal connections to the relay outputs and a source must therefore always be
connected to one of the relay terminals for the output to work.
The RTCU NX-910 device offers a very advanced power management which makes it possible to
have one or more outputs enabled while the RTCU is in low-power mode. Please consult the
RTCU IDE on-line help for more information.
Relay output terminals
Terminal Name
Description
R1A
R1B
Contact set for relay output 1.
R2A
R2B
Contact set for relay output 2.
R3A
R3B
Contact set for relay output 3.
R4A
R4B
Contact set for relay output 4.
Load noise
If highly inductive loads (such as high-power contactors) are connected to the relays, it may in
certain cases be necessary to externally connect a clamping diode parallel with each inductive DC
load or connect an RC snubber circuit parallel with each inductive AC load.
For DC applications Vishay UF5405-E3/54 or similar is recommended and for AC applications
AMPOHM FE-SP-HDR23-47/100 (47nF/100 ohm) or similar is recommended.