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Configuring the dio channels to generate alarms – Measurement Computing WLS-TEMP User Manual

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WLS-TEMP Specifications

18

Figure 10. Schematic showing switch detection by digital channel DIO0

Caution! All ground pins on the WLS-TEMP (pins 9, 19, 28, 38) are common and are isolated from earth

ground. If a connection is made to earth ground when using digital I/O and conductive
thermocouples, the thermocouples are no longer isolated. In this case, thermocouples must not be
connected to any conductive surfaces that may be referenced to earth ground.

For general information regarding digital signal connections and digital I/O techniques, refer to the Guide to
Signal Connections
(available on our web site at

www.mccdaq.com/signals/signals.pdf

).

Configuring the DIO channels to generate alarms

The WLS-TEMP features eight independent temperature alarms. All alarm options are software configurable.
Remote alarm configuration is supported.

When a digital bit is configured as an alarm, that bit is configured as an output on the next power cycle and
assumes the state defined by the alarm configuration.

Each alarm controls an associated digital I/O channel as an alarm output. The input to each alarm is one of the
temperature input channels. You set up the temperature conditions to activate an alarm, and also the output state
of the channel (active high or low) when activated. When an alarm is activated, its associated DIO channel is
driven to the output state specified.

The alarm configurations are stored in non-volatile memory and are loaded on power up. The temperature
alarms function in wireless operations and while attached to the USB port on a computer.

You can configure alarm settings when you connect the WLS-TEMP locally to the computer through the USB
port, or when operating it remotely through the wireless interface.