<script type="text/html" data-help-name="rbe"> <p>Report by Exception node - only passes on data if the payload has changed.</p> <p>It can also block unless, or ignore if the value changes by a specified amount.</p> <h3>Inputs</h3> <dl class="message-properties"> <dt>payload <span class="property-type">number | string | (object)</span> </dt> <dd>RBE mode will accept numbers, strings, and simple objects. Other modes must provide a parseable number.</dd> <dt class="optional">topic <span class="property-type">string</span> </dt> <dd>if specified the function will work on a per topic basis.</dd> <dt class="optional">reset<span class="property-type">any</span></dt> <dd>if set clears the stored value for the specified msg.topic, or all topics if msg.topic is not specified.</dd> </dl> <h3>Outputs</h3> <dl class="message-properties"> <dt>payload <span class="property-type">as per input</span> </dt> <dd>If triggered the output will be the same as the input.</dd> </dl> <h3>Details</h3> <p>In RBE mode this node will block until the <code>msg.payload</code>, (or selected property) value is different to the previous one. If required it can ignore the intial value, so as not to send anything at start.</p> <p>In the Deadband modes the incoming value must contain a parseable number and will block unless the change is greater than + or - the band gap away from a previous value.</p> <p>Deadband also supports % - only sends if the input differs by more than x% of the original value.</p> <p>The Narrowband modes will block if the incoming value change is greater than + or - the band gap away from the previous value. Useful for ignoring outliers from a faulty sensor for example.</p> <p>Both Deadband and Narrowband allow comparison against either the previous valid output value, thus ignoring any values out of range; or the previous input value, which resets the set point, thus allowing gradual drift (deadband), or a step change (narrowband).</p> <p><b>Note:</b> This works on a per <code>msg.topic</code> basis. This means that a single rbe node can handle multiple different topics at the same time.</p> </script>