verified connector library

Carlo Gavazzi EM330/EM340 energy meter

Register map(s) for this device, each at the trust rung it earned. Addresses are 0-based as on the wire; word order and scaling are only confirmed at the hardware-verified rung.

interop-verified

Read + decoded cleanly over a real network vs an independent third-party Modbus test server (transport and framing; reads are remapped into the server's register window, so the map's own addresses are NOT exercised). Does NOT prove word order/scaling against the actual device.

pointaddress (0-based)typescaleunit
v_l1_n0U32LE0.1V
v_l2_n2U32LE0.1V
v_l3_n4U32LE0.1V
v_l1_l26U32LE0.1V
v_l2_l38U32LE0.1V
v_l3_l110U32LE0.1V
a_l112U32LE0.001A
a_l214U32LE0.001A
a_l316U32LE0.001A
w_l118U32LE0.1W
w_l220U32LE0.1W
w_l322U32LE0.1W
va_l124U32LE0.1VA
va_l226U32LE0.1VA
va_l328U32LE0.1VA
var_l130U32LE0.1var
var_l232U32LE0.1var
var_l334U32LE0.1var
v_l_n_sys36U32LE0.1V
v_l_l_sys38U32LE0.1V
w_sys40U32LE0.1W
va_sys42U32LE0.1VA
var_sys44U32LE0.1var
pf_l146I160.001
pf_l247I160.001
pf_l348I160.001
pf_sys49I160.001
hz51I160.1Hz
kwh_pos_tot52U32LE0.1kWh
kvarh_pos_tot54U32LE0.1kvarh
kw_dmd56U32LE0.1W
kw_dmd_peak58U32LE0.1W
kwh_pos_partial60U32LE0.1kWh
kvarh_pos_partial62U32LE0.1kvarh
kwh_pos_l164U32LE0.1kWh
kwh_pos_l266U32LE0.1kWh
kwh_pos_l368U32LE0.1kWh
kwh_neg_tot78U32LE0.1kWh
kvarh_neg_tot80U32LE0.1kvarh
thd_a_l1130U32LE0.01%
thd_a_l2132U32LE0.01%
thd_a_l3134U32LE0.01%
thd_v_l_n_sys136U32LE0.01%
thd_v_l1_n138U32LE0.01%
thd_v_l2_n140U32LE0.01%
thd_v_l3_n142U32LE0.01%
a_n152U32LE0.001A

link settings as documented (unverified): RTU; default 9600 8N1; unit ID 1; FC 03,04,06,08; Functions 03h and 04h have exactly the same effect and can be used indifferently. Maximum 50 registers can be read with a single request.

bench facts as documented (unverified)
terminalsA-, T
termination120 ohm 1/2W 5% resistor between line B and A
shield/groundConnect shield to GND on master side only
wiring notesSuggested to use AWG24 balanced pair cable and add a third wire for GND connection.
max registers/read50
response timeout500 ms
inter-frame delay40 ms
broadcastsupported
sentinel values7FFFFFFFh (or EEE on display) for overflow
protocol notesT null: Max interruption time during the request frame is 2.5 char
model register11
serial register20480
firmware register770
identification notesModel register is Carlo Gavazzi Controls identification code. Serial register is Letter 1 to Letter 7 starting at 5000h.
certificationsMID certification (PFA and PFB)
doc revisionVersion 2 Revision 17 (July 05, 2021)

generated by gemini:gemini-3.5-flash · harvested from https://www.gavazziautomation.com/fileadmin/images/PIM/OTHERSTUFF/COMPRO/EM330_EM340_ET330_ET340_CP.pdf (Carlo Gavazzi); manual-faithful — the document's claims, panel risk: ELEVATED — panel is not confident; proved interop-verified on 2026-06-10 · recorded 2026-06-10

The trust ladder

Each rung states what it proved and what it did not. Gray until proven; green is earned by hardware only.

Have a device that isn't here? Upload its register map — generation is free, and the connector earns its rung by being proven, not claimed.

Need it proven on your own device? Hardware verification — if it doesn't verify, you don't pay.

Building a platform? License the verified library — machine-readable maps, firmware matrix, API access.