Hi,
The power socket has failed where my main switch and patch panels are and there is no near alternative.
I realised I have a rb751g-2HnD and it has POEin
Also I have a Cisco SG300-10PP with 10 POEout+
So I could move the rb751g-2HnD to the switch room and power it with the Cisco - Sweet
However after looking at some specs it seems the RB passive POEin and the Ciscos 802.3at won’t play together 
A point to note is that I have split my Cat5e so it supplies two Ethernet 100Mb ports!
Looking at Amazon for express delivery Monday:-
https://www.amazon.co.uk/dp/B075V3NVFK/_encoding=UTF8?coliid=IZPMADPPV73BD&colid=CITMOXNH0MVG&psc=1
Injector: RJ45 Male + Power In to RJ45 Female
Splitter: RJ45 Female to RJ45 Male + Power Out
Supports: DC 12V-48V
Power plug / jack: 2.1 * 5.5mm / 0.9 * 2.2in
Power Pins: 4,5 + and 7,8
Length:16cm
Transmission distance: 30-100 m,If your transmission distance is more than 100 m, please use adjustable QS brand centralized power supply.
Use pair of this with QS brand adjustable centralized power supply,the transmission distance is about 80 m.
Use non-adjustable 12V power supply,the transmission distance is 50-80 m.
(Note: according to the voltage of the power supply voltage, line quality.)
Please try to use the oxygen-free copper pure copper wire. Use better power to reduce the instability.
Note: Use 12V-15V SPOE switch output , please confirm the output is 12V ,not 48V.
This section does not with voltage transformer function.
Use the switch with output 12V, power to 90W-110W, transmission distance is about 100 m.
Use the switch with output 15V, power more than 90W, transmission distance could up to 100 m.
https://www.amazon.co.uk/dp/B00B5VIE0Q/_encoding=UTF8?coliid=I1UMB0CU6K2YFT&colid=CITMOXNH0MVG&psc=0
PoE (Power over Ethernet) is a technology used to safely pass electrical power, along with data, over Ethernet cabling. By using free wires in the Ethernet cabling, PoE is a new exciting technology. By using PoE you can easily extend the range (30 metres) of your Ethernet devices without the need for a seperate power cable (to the loft, the conservatory etc.). Compatible with all types of different devices such as IP telephones, IP cameras, wireless LAN access points and much more. The unit uses Phantom-powering techniques to combine Data and DC power onto Gigabit Ethernet data pairs 4/5 and 7/8 SPECIFICATIONS: POE protocol: passive POE pins: compatible 4,5(+); 7,8(-), Midspan power supply mode Connectors 2.1*5.5mm DC 1, Support BASE-100/1000T, 1000Mbps Gigabit ethernet requirements. 2, Separate data and current with capacitance protection, and grounded&shielded RJ45 plugs to acheive better resistance on EMI/RFI, sametime for much better communication on gigabit ethernet and avoid crosstalk , interruption etc on data transfer. 3, Support 9-56V output ,Max 2A for power over ethernet on PD, also comvinience for UPS power. 4, With shielding and seprated compacitance protection, the voltage and current are delivered more stable, protect devices from static and inrush current damage. Reinforce the power over ethernet delivery distance to 80-100 meters. 5, Support 48V/1A for your POE switch networking, and wireless AP, Wireless transmitter,POE camare, VoIP phone etc DC Input Voltage: 9-48V +/- 5% max 56V DC Output Voltage: 9-48V +/- 5% Max Output Current: 2A max Ethernet Cable: TIA/EIA 568 Cat.5e
https://www.amazon.co.uk/Solwise-POE-EPE1212-Basic-Passive-Injector/dp/B00B27HS46/ref=cm_wl_huc_item
9-48V/1a
Data PIN 1/2 & 3/6
Power PIN 4/5+ & 7/8-
Would one of the above do the job?
I don’t mind loosing one port for power so long as I can still RX/TX over the other one.
I’m only using the rb751g-2HnD as a switch at the moment.
[Switch room: rb751g-2HnD: port1 POEin another port ADSLin]------ 1 Cat5e split to provide two ports --------[ADSL room: port1 POE port2 ADSL]
Does anyone know what’s the size of the plug of the power supply supplied with the rb751g-2HnD?
Thanks