Resetting Hour and Event Meters Video at Inductive University

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[00:00] Hour Meter and Event Meter items can be configured to reset their accumulated values in two different ways. First, the item can be configured to reset on a condition. For example, the transition of a Boolean tag to false. Or the item can be configured in bidirectional mode. In which case, the reset value will come from the database. We'll look at each of these with a brief example. Here we have an Hour Meter, configured on a Boolean tag, set to to increment while the value is true. If we start the group, which is set to the right to the first row of an example table, we will see the value accumulate and get updated in the database. If we want this value to reset, when a separate Boolean tag becomes false, we can bring the tag into the group, set that tag to Read Only, so that it doesn't get written to the database, and then configure the Reset on Condition field in our Hour Meter tag. We'll select our new Boolean tag, and tell it to reset on zero or false condition. Saving the group in this state, we see that the item will begin to accumulate as we would normally expect. At any time, can set our Boolean reset tag to false, and we'll now see the value reset to zero, and begin accumulating again. The other way to reset Hour and Event Meters is to configure the item to be bidirectional. That way, the value can be reset from the database. So, to do this, we can either set the bidirectional mode on the group, or on the item. Since we care about the item in this case, we'll do that there. Since the Hour Meter is accumulating constantly, it's important for us to select the bidirectional mode that will let the database value win if it changes on both sides. Doing this and saving the group, we now see that the value will begin to accumulate as we would expect. Looking at the database, we see the updates coming in at a constant rate. The difference now is that if we edit the database, and set the value back to zero, the value will be written to the item, and begin accumulating from there. One small point is that the value could be reset to any particular value. For example, if I write 100... that will become the new value and the accumulation will begin from that point. So, while this is normally used for resetting, it can also be used for adjustment, which makes it a little bit more flexible than the other reset method. Also, the item will begin to accumulate from the last value in the database each time the group starts, which can often be useful.

Hour Meter and Event Meter items can be configured to reset their accumulated values in two different ways. First, the item can be configured to reset on a condition. For example, the transition of a Boolean tag to false. Or the item can be configured in bidirectional mode. In which case, the reset value will come from the database. We'll look at each of these with a brief example. Here we have an Hour Meter, configured on a Boolean tag, set to to increment while the value is true. If we start the group, which is set to the right to the first row of an example table, we will see the value accumulate and get updated in the database. If we want this value to reset, when a separate Boolean tag becomes false, we can bring the tag into the group, set that tag to Read Only, so that it doesn't get written to the database, and then configure the Reset on Condition field in our Hour Meter tag. We'll select our new Boolean tag, and tell it to reset on zero or false condition. Saving the group in this state, we see that the item will begin to accumulate as we would normally expect. At any time, can set our Boolean reset tag to false, and we'll now see the value reset to zero, and begin accumulating again. The other way to reset Hour and Event Meters is to configure the item to be bidirectional. That way, the value can be reset from the database. So, to do this, we can either set the bidirectional mode on the group, or on the item. Since we care about the item in this case, we'll do that there. Since the Hour Meter is accumulating constantly, it's important for us to select the bidirectional mode that will let the database value win if it changes on both sides. Doing this and saving the group, we now see that the value will begin to accumulate as we would expect. Looking at the database, we see the updates coming in at a constant rate. The difference now is that if we edit the database, and set the value back to zero, the value will be written to the item, and begin accumulating from there. One small point is that the value could be reset to any particular value. For example, if I write 100... that will become the new value and the accumulation will begin from that point. So, while this is normally used for resetting, it can also be used for adjustment, which makes it a little bit more flexible than the other reset method. Also, the item will begin to accumulate from the last value in the database each time the group starts, which can often be useful.

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