Weidmuller WI-I/O-9-U2: Wireless Mesh I/O & Gateway User Manual V1.2.2 - Manual (Page 18)

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reduced to 0.5A at 60°C. If using a battery it is recommended a 10A inline fuse be fitted
as prevention against battery short circuit.
If utilising option 1 above and the Primary Supply fails the Battery Supply will continue
to power the module without interruption to the operation.
The Supply and Battery charging terminals are hosted on the 4-way connector on the
bottom edge of the module labelled “Supply”
Both Supply and Battery connections have reverse polarity and over voltage protection.
The power supply should be CSA Certified Class 2 approved for normal operation.
If the device is being used in a Class I Div 2 explosive area, the supply must have Class
I Div 2 approval.
When powering the module the power source must be able to provide enough current to
power all module operations, i.e. Quiescent current, Peak Transmit current, Digital and
Analog I/O including loop supply and Battery charging (if applicable).
To calculate the Power Supply current limit, use the following criteria.
Current @ 13.8V @ 24V
Quiescent Current of the module 200mA 115mA
Module Maximum I/O (4xAI, 2xAO, 8xDO) 500mA 290mA
Peak Transmit current 500mA 290mA
External Expansion I/O 1000mA 575mA
Battery charging N/A 575mA
The following table shows typical +24V Supply current limits with different module
options enabled. Note: Transmit current is not added as
it’s not a constant.
Expansion I/O No Expansion I/O
No Battery fitted (no charging)
1270mA 695 mA
Battery fitted
1555mA 980 mA
The following table shows typical +13.8V Supply current limits with different module
options
enabled. . Note: Transmit current is not added as it’s not a constant.
Expansion I/O No Expansion I/O
Current Limit
2200mA 1200 mA
E.g. If a module is powered by a 24V DC supply and there is no backup battery
connected and it has expansion I/O fitted the minimum current needed is 1.3 Amps
@24V (32Watts).
This is allowing for 290mA Peak Transmit current and up to 1 Amp for expansion I/O