Brultech - NodeLink reporting different wh than GEM

[mblitz]

I have GEM/NodeLink/isy/emoncms working.  The channels show up in NodeLink, isy and enomcms, but the wh reported to isy and emoncms are not the total watt hours reported by GEM.

 

For example:

    - The total watt hours reported by GEM for channel 1 is 29979.31

    - The total watt hours reported on the NodeLink GEM page is 134617.47

    - The wh reported in emoncms is 29.77

    - The wh reported in isy is 60.84

 

These reading are taking over a few second/minutes, so I expect some divergence, but not orders of magnitude.  The wh reported by emoncms is approximately half of what they isy reports.

 

thanks,

marty

 

[larryllix]

I have GEM/NodeLink/isy/emoncms working.  The channels show up in NodeLink, isy and enomcms, but the wh reported to isy and emoncms are not the total watt hours reported by GEM.

 

For example:

    - The total watt hours reported by GEM for channel 1 is 29979.31

    - The total watt hours reported on the NodeLink GEM page is 134617.47

    - The wh reported in emoncms is 29.77

    - The wh reported in isy is 60.84

 

These reading are taking over a few second/minutes, so I expect some divergence, but not orders of magnitude.  The wh reported by emoncms is approximately half of what they isy reports.

 

thanks,

marty

Knowing nothing about these systems, but much experience with legal billing pulse metering I see a few things that may help give you some sleuthing clues.

 

The 29979 Wh in the GEM may be showing up as 29.x kWh in emoncms (whatever that is)

This may also be showing up as 60.84 kWh in ISY as there are a few pulse transmission methods used in metering. Some systems count every change as a pulse and this looks to be double...maybe?

 

 

The NodeLink page count looks unexplainable but may have some remnants from a previous life. Try rebooting NodeLink and see what the count does.

 

Some systems used cumulative Wh count tallies so that every time a count is updated it was added to the previous count. If one has a comm failure or the count is messed up the next one can self-correct the tally.

 

Of course this is all based on a pulse counting system and once the pulses are counted and converted to count registers, none of this may apply, so take with a grain of salt.

[mblitz]

You may be correct for the isy.  It showing units of "kWh", so that explains the magnitude for that.  But emoncms is reporting units of "wh".

 

I've rebooted the RPi and isy several times during the day, so I don't think its remnants.

 

Another problem I'm seeing is that if a channel's amps/watts are 0, the zero amps/watts data is being sent to the emoncms and updated, but the wh is not being sent, so it is stale for a long time.

 

For example, channel 30 is showing 0 for amps/watts, and was updated 2 second ago, but the wh is 41.94 and has not been updated for 9 minutes.

[larryllix]

You may be correct for the isy.  It showing units of "kWh", so that explains the magnitude for that.  But emoncms is reporting units of "wh".

 

I've rebooted the RPi and isy several times during the day, so I don't think its remnants.

 

Another problem I'm seeing is that if a channel's amps/watts are 0, the zero amps/watts data is being sent to the emoncms and updated, but the wh is not being sent, so it is stale for a long time.

 

For example, channel 30 is showing 0 for amps/watts, and was updated 2 second ago, but the wh is 41.94 and has not been updated for 9 minutes.

On the last statement I don't see any relationship or logic there.

Wh should be a permanent reading and may not be updated until any change is detected.

 

O amperes and 0 Watts will not change an existing watthourreading. It's already accumulated.

Above 0 readings for amperes and power should advance the Wh reading, though. Most are not resettable, either, for a reason.

[mblitz]

On the last statement I don't see any relationship or logic there.

Wh should be a permanent reading and may not be updated until any change is detected.

 

O amperes and 0 Watts will not change an existing watthourreading. It's already accumulated.

Above 0 readings for amperes and power should advance the Wh reading, though. Most are not resettable, either, for a reason.

 

That is true, it should always be increasing, but for other channels, such as channel 1, I see the watt hours change to 37.01, 74.03, 10.01, 40.04, 80.1

 

That does not seem to be always increasing.

[larryllix]

That is true, it should always be increasing, but for other channels, such as channel 1, I see the watt hours change to 37.01, 74.03, 10.01, 40.04, 80.1

 

That does not seem to be always increasing.

That does seem a lttle random. Is there a way two channels could be hitting on the same variable?

I am not familiar with these boxes or how it works. Teken or Scott should be more versed with this stuff.