sub-DB reading higher than feeder DB

Are we talking here of instantaneous load readings ? if so the load may have changed perhaps substantially, between taking readings  in the different locations.

Also double check that the same units were used for all readings, Amps ?  KW ? KVA ? All three phases measured, or just one ?

Or are we talking of true consumption in KWH over a reasonable interval such that slightly different times of taking the readings are of little consequence.

If true consumption IN THE SAME UNITS is being measured, then the reported results are most unlikely. If however Kva hours are measured at the distant building, and Kw hours are measured at the main building, then a higher reading at the distant building is possible if the power factor is bad enough.

If none of the above, then one of the meters must be either faulty or being read incorrectly, or is wrongly connected.

Common errors include a blown fuse in the “voltage” circuit of one or two phases, or wrong ratio current transformers fitted, or one current transformer the wrong way round.

Electricity meters are generally reliable, errors in connections or in the programming of modern digital meters are more likely. As are reading errors is a menu has to be navigated.

The “total units” reading is generally what is required. Accidentally reading only “night time units” on the main meter, but “total units” on the distant one could give the results reported.

Are we talking here of instantaneous load readings ? if so the load may have changed perhaps substantially, between taking readings  in the different locations.

Also double check that the same units were used for all readings, Amps ?  KW ? KVA ? All three phases measured, or just one ?

Or are we talking of true consumption in KWH over a reasonable interval such that slightly different times of taking the readings are of little consequence.

If true consumption IN THE SAME UNITS is being measured, then the reported results are most unlikely. If however Kva hours are measured at the distant building, and Kw hours are measured at the main building, then a higher reading at the distant building is possible if the power factor is bad enough.

If none of the above, then one of the meters must be either faulty or being read incorrectly, or is wrongly connected.

Common errors include a blown fuse in the “voltage” circuit of one or two phases, or wrong ratio current transformers fitted, or one current transformer the wrong way round.

Electricity meters are generally reliable, errors in connections or in the programming of modern digital meters are more likely. As are reading errors is a menu has to be navigated.

The “total units” reading is generally what is required. Accidentally reading only “night time units” on the main meter, but “total units” on the distant one could give the results reported.