Ubiquiti CM-RJ45-1G
Ubiquiti · SFP transceiver, 1000BASE-T · CM-RJ45-1G
what it is
A 1000BASE-T transceiver (Ubiquiti) in the SFP form factor, part number CM-RJ45-1G. Production year stored in memory: 2023. Revisions seen in the examined units: A1. Units examined: 10.
what we read from it
This is a copper transceiver (DAC cable or RJ45 port). It has no optical diagnostics by design: there is no laser and no light to measure. The switch reads its identity: manufacturer, part number, serial number and revision.
A full read of the transceiver memory gives it a diagnostics score of 2 out of 15 — counted are: presence of measurements, manufacturer thresholds, alarm flags set by the transceiver itself and software loss-of-signal indication.
what the transceiver memory declares
Transceiver memory read directly from a Cisco switch (show idprom, page A0) — 2 units. Each item gives the memory byte and value it comes from; we do not show serial numbers, exact dates or the vendor-reserved area.
- Module type: SFP/SFP+ (byte 0 = 0x03).
- Connector: RJ45 (byte 2 = 0x22).
- Standard (compliance code): 1000BASE-T (bytes 3, 6 = 0x00, 0x08).
- Nominal rate: 1300 MBd (byte 12 = 0x0D).
- Hardware signals: none (byte 65 = 0x00).
- Optical diagnostics (DDM): not declared (byte 92 = 0x00).
- Extended options: none (byte 93 = 0x00).
- SFF-8472 diagnostics revision: not declared (byte 94 = 0x00).
- Chip vendor identifier (OUI): filled (bytes 37-39).
- Memory checksums: valid (bytes 63 and 95).
- Vendor-reserved area: empty (bytes 96-127).
- Vendor alarm thresholds: not shown — transceiver does not declare diagnostics.
- Production year stored in memory: 2023.
A declaration in memory is not the same as a reading: none of the switches examined showed diagnostic measurements (Cisco WS-C3750X-12S-S, UniFi Switch Aggregation, UniFi Switch Aggregation Pro).
how we checked
The result depends on what the transceiver was read with — the same switch model in a different installation can show different data. That is why each reading is recorded separately:
- Cisco Catalyst 3750-X 12S-S (Cisco WS-C3750X-12S-S), firmware
15.2(4)E10— transceiver memory and diagnostics table read from the console, 2026-10-19: diagnostics not shown (2 units). Visible data: manufacturing date, reach per fiber type, standard (compliance code), chip vendor identifier, memory checksums, identity (manufacturer, part number, serial number, revision). Cable test: not tested. - UniFi Switch Aggregation, firmware
7.4.1.16850— transceiver fields in the UniFi controller, 2026-10-17: diagnostics not shown (2 units). Visible data: transmitter fault indication (TX_FAULT), standard (compliance code), identity (manufacturer, part number, serial number, revision). Cable test: not tested. - UniFi Switch Aggregation, firmware
7.5.15.17146— transceiver fields in the UniFi controller, 2026-10-17: diagnostics not shown (1 unit). Visible data: transmitter fault indication (TX_FAULT), standard (compliance code), identity (manufacturer, part number, serial number, revision). Cable test: not tested. - UniFi Switch Aggregation Pro, firmware
7.4.1.16850— transceiver fields in the UniFi controller, 2026-10-17: diagnostics not shown (6 units). Visible data: transmitter fault indication (TX_FAULT), standard (compliance code), identity (manufacturer, part number, serial number, revision). Cable test: not tested.
The same transceiver in other switches and a comparison with other models: what each device shows.
what we cannot read
- Nothing significant — the transceiver memory was read in full.
parameters the transceiver returns
The list shows WHAT the device exposes — including parameters we do not use ourselves. There are no values here at all: it is a catalog of capabilities, not a reading from anyone's network. It is not a closed list either — explanation below the table.
10 parameters
| parameter | type |
|---|---|
data_produkcji | date |
numer_czesci | text — part number (PN) |
numer_seryjny | text |
oui_producenta | text — chip vendor identifier |
producent | text — vendor name from transceiver memory |
rewizja | text |
sumy_kontrolne | boolean — transceiver memory validity |
usterka_nadajnika_tx_fault | boolean |
zasiegi_wlokien | numbers (m / km) for OM1–OM3 and single-mode fiber |
zgodnosc | text — standard (e.g. 1000BASE-LX) |
This is not a closed list. It comes from reading a unit we had access to — it shows what we managed to retrieve, not everything the device can return. A different firmware version, hardware variant or reading path can expose fields that are not here. If you are interested in a specific unit and a specific value — please ask; there is a good chance it can be obtained, even if you do not see it below.
List source: reading of 10 working units (as of 2026-10-19). The list is the sum of what we observed — more units reveal more parameters, so numbers for different models are not directly comparable.