5 Annex. Meter Forms

The service type determines what meter form is being implemented and how the Metrology DSP core interprets and processes the ADC values.

Table 5-1. Service Types
TYPE	Service Type		Elements	V inputs [Voltage Channels]	#I inputs [Current Channels]	P/S
0	Three-phase 4-wire Wye (3-element)	3P4WY_3E_3V3I	3	3 [v1, v2, v3]	3 [i1,i2,i3]	P
1	Three-phase 4-wire Delta (3-element)	3P4WD_3E_3V3I	3	3 [v1, v2, v3]	3 [i1,i2,i3]	P
2	Three-phase 4-wire Wye (2-½ element) †1	3P4WY_2p5E_2V3I	2 1/2	2 [v1, v2, v3]	3 [i1,i2,i3]	P
3	Three-phase 4-wire Delta (2-element) †2	3P4WD_2E_3V2I	2	3 [v1, v2, v3]	2 [i1,i3]	P
4	Three-phase 3-wire Delta (2-element)	3P3WD_2E_2V2I	2	2 [v1, v3]	2 [i1,i3]	P
5	Two-phase 3-wire Network (2 element) †3	2P3W_2E_2V2I	2	2 [v1, v3]	2 [i1,i3]	P
6	Single-phase 3-wire (1-½ element) †4	1P3W_1p5E_1V2I	1 1/2	1 [v1]	2 [i1,i3]	P
7	Single-phase 2-wire (1 element)	1P2W_1E_1V1I	1	1 [v1]	1 [i1]	P/S
8	Single-phase 3-wire (1 element) †5	1P3W_1E_2V1I	1	2 [v1, v3]	1 [i1]	P

The next chapters show the configuration for each Service Type.

†1 For the Three-phase 4-wire Wye 2-½ element meter, any one phase voltage may be selected to be the missing phase, and the missing voltage will be internally imputed from the other 2 phase voltages.

†2 For the Three-phase 4-wire Delta 2 element meter, one current sensor is used to measure the collective current of two phases, (IA-IB). All phase voltages VA, VB and VC are measured.

†3 For the Two-phase 3-wire 2 element meter, three common service types with two separate voltage phases and two separate currents may be metered by this mathematically identical service type. These are commonly known as:

Two-phase 3-wire Network (2p3WN)
Single-phase 3-wire 2 element (1p3W_2E)
Two-phase 5-wire (2p5W) with 2 current sensors each used to measure the collective currents of (IA-IA’) and (IC-IC’)

†4 For the Single-phase 3-wire 1-½ element meter where only one phase-phase voltage, VAC, is measured but 2 current elements are measured.

†5 For the Single-phase 3-wire 1 element meter where two individual phase voltages, VA & VC, are measured but only one current element is measured.

METER_TYPE contains all the possibilities for the Service Type available and their configurations.