I sent an email inquiry to Grahams about the Hydra and this is their reply:
“We are afraid we cannot make the Hydra for 115v use as this is twice the voltage and the cable we use is not rated for this.”
I’m just wondering what cable do they use… and does a power cord really have to be designed specifically for either 115v or 230v, but not both?
Twice the Voltage is not right. 115V is half of 230V. Twice the Current, yes.
AFAIK, Grahams use the standard Naim Mains Lead to make Hydra’s from.
I would - gently - query Grahams response - and pls report back.
I wouldn’t entertain one of those home brew jobs for free.
I recall when looking for the flex specification used by the power line lite that it was rated at 10amps. So 10 amps at 115V gives a limit 1150watts across all the Hydra devices.
Of course in the US they don’t have plug fuses, so not sure what rules there are about flex current capacities.
I think their code puts a limit (10A, 15A?) on the maximum current of a normal domestic circuit.
I have used Grahams Hydra (and power block) for donkey’s years. They seem to work well and have been 100% reliable. I suspect a slip in conversation (it’s twice the amps, no?).
It may be that they don’t get many requests like this and can’t easily source a cable rated appropriately. Specialist manufacturers are likely to fare better.
It may be worth noting that (for example) Custom HiFi Cables say on their website: -
We fit the MK toughplug as standard to our PowerBlack cables and a transparent UK mains plug to our Regular Shielded cables as standard, but can also fit mains plugs for Europe (Schuko type), Australia and the US, as well as male IEC connectors if you need an IEC-IEC cable. We can also fit multi-way Hydra mains plugs if you want multiple outputs from a single mains plug (UK plug only, 2 to 4 outputs). In addition, we hold several silver-plated versions of these plug types in stock, so please ask if you have a specific request.
Do let us know your final solution!
FWIW i’ve been using a Grahams hydra in Canada since I left the UK 20 years ago. All i did was replace the uk plug with a north american one.
I have a vague recollection that some of Naim’s non-UK mains leads are a little thicker than the UK version which I think uses .75mm wires. Perhaps it’s the thicker wires that can’t easily be joined to make a Hydra?
In the USA as standard we have 115-120V @ 15 amps
One can increase that to 20amps if the Circuit Breaker is up graded to 20amps and wiring is at least 12awg… I have two dedicated circuits 20amps with 10awg wire.
Have used one for many years. It just works…
It is likely not the voltage rating as such, but half the voltage means twice the current for the same load - so crudely speaking the conductors need to be around twice the cross sectional area for the same safety margin. And that is before factoring in the question of whether the circuit feeding the cable has an adequately low current rating to protect the cable in the event of a fault if there is no protective fuse in the plug, so it is unsurprising that a UK manufacturer may prefer to not get involved.
I did request for a clarification from Grahams. Unfortunately I have not received an email reply from them yet.
As indicated in my post, their statement was quite understandable and meaningful, and didn’t need any further explanation, though of course there is scope for more detail - but whether that is worth their time for a market area they clearly are not pursuing is another matter.