Connector

[busman 25]

Hi there, I have an uprated 16 volt 6 amp power supply which I wish to use with my Railmaster DCC elink unit, which at the moment struggles with more than one loco in use at the same time, not wanting to cut the small tound connecting plug off my existing power supply, could any one give me the size details for this connector so that I can purchase a new one for the uprated power supply.

Cheers 

[Chrissaf]

I will answer your question, but I would advise you not to use a power supply higher than 4 Amps.....5 Amps absolutely maximum and even then with a warning caveat, and 15 volts not 16 volts DC.

.

For one thing the circuitry inside an eLink is designed to 'short circuit' trigger at 3 Amps so even if you had a 6 Amp supply you are not going to get 6 Amps of power out of it. The eLink will limit that down to 3 Amps and then go into 'short circuit' protection mode if more than 3 Amps is drawn. Internally, the power input line has a auto-resettable 3 Amp fuse as well for emergency protection backup.

.

Secondly, by going higher than the designed for 4 Amps, you are in risk of damaging the eLink. There is already at least one post on this forum where a perfectly good working eLink was burnt out by a forum member using a non Hornby 5 Amp supply. For some unknown reason the eLink did not like the output of the non Hornby power supply and the internal self protection did not kick in. These type of power supplies are 'Switch Mode' power supplies and the DC outputs can contain noise inducing harmonic frequencies that can upset some types of connected IC circuits. It is possible that the official Hornby power supply circuit is somehow tuned to the controller circuits.

.

Also, the Hornby eLink is designed for 15 volt operation, not 16 volt. Internally there is a 'voltage regulator' to generate a lower 3.3 volt rail for the internal IC circuitry. By increasing the input voltage from 15 to 16 volts you risk stressing the power input regulators and causing them to generate more heat, this could potentially lead to premature eLink failure.

.

So go ahead at your risk. The DC connector is 6.3mm outside barrel diameter and the inner pin is 3.0mm. An inner pin of 3.1mm is compatible and is a more easily sourced connector.

.

Here for example.

OR

Here

.

[ColinB]

I hate to say this but I have great difficulty in believing a 5 amp supply instead of a 4 amp supply would cause damage, unless there was a fault on the input stage of the Elite. It should draw only what it needs. Generally current limiting is done via a sense resistor in the output, that triggers a circuit to feedback to the regulator to disable the output, I have designed these in the past. Generally, you limit the input current because it means you can use a cheaper transformer. I also have difficulty believing that 16 volts instead of 15 volts would cause damage, but I bow to your better judgement. If it was 18 to 20 volts I could believe it. I suspect the person who blow up the Elite was probably using an unregulated 16 volt supply, possibly from China, that would definitely do it.

[Chrissaf]

Colin,

.

Regarding the current. I can only repeat what I have seen posted on the forum by others that have been affected. As you say maybe an underlying fault was present (eLink not an Elite by the way). But the reported burn-out was an eLink that was reported as working 100% fine on the original Hornby 1 Amp power supply, but burnt out when a non Hornby 5 Amp supply was attached**. I agree that in theory the eLink should just draw what it needs, but the point that the eLink can't provide more than its designed current output regardless of the input current available still stands as a definite.

.

Note** the power supply in question was actually quoted by model number in the post and was not an unregulated 16 volt supply. It was a 15 volt 5 Amp Laptop Switch Mode power supply that had the correct sized DC connector factory fitted as standard.

.

With regards the voltage. I'm just erring on the side of caution and did use the phrases "you risk" and "this could potentially". The voltage regulator is linear (I have looked up the data-sheet for it) thus it does have to dissipate the excess voltage as heat and the output is only 3.3 volts, so it is already having to drop a fair amount of voltage from the input.

.

The last point I make, is that if posts on this forum are anything to go by there are a relatively high number of eLink failures due to burnt out components. To my mind, this is a possible indication of a circuit design that is on the edge of circuit component tolerances, so an additional 1 volt increase to the input could potentially make a noticeable difference to longer term reliability.

[RDS]

The most reliable and safest method of increasing the power available to elink is to use the 4 Amp Hornby Power Supply, that comes with the Elite but also available separately as Hornby Item P9300.

[Chrissaf]

PS - I would add that if the current eLink power supply is struggling to power more than one loco (I assume it is the standard default 1 Amp power supply), Then I would suggest that the 1 Amp power supply may actually be faulty. It would not be the first eLink 1 Amp power supply to be reported on this forum that exhibited the reported lack of power issue. The reported issues have been subsequently reported to have gone away when the 1 Amp supplies were either replaced either with another new 1 Amp supply under Warranty or with a P9300 4 Amp supply as a 'paid for' upgrade as intimated by RDS above.

.

Also, the eLink itself takes a fair chunk of the 1 Amp just to run itself internally, leaving little left for running locos. This can be compounded if the locos in question are older more current hungry locos that have been DCC converted. Then there might be other items drawing power from the eLink. Like 'Accessory Decoders' for example or passenger coach lighting, these can all be a drain on the eLink 1 Amp power supply current resources.

[96RAF]

You are confusing me Colin.

The OP started out talking about eLink, which Chris discussed, then you flipped it to Elite, a completely different beast.

One thing is for sure if you stick to kit from the same manufacturer your chances of it working as designed are a tad higher than plugging in some bogey kit from knock-off land.

[Chrissaf]

One final comment for new forum member Busman 25.

.

Some of the replies above to your original question are quite long ones. It would be appreciated if you didn't try to reply by using the 'Blue button with the White arrow'. This is not a reply to this post button.

.

If you want to reply to any of the posts, scroll down and write your reply in the reply text box at the bottom of the page and click the Green 'Reply' button.

.

See also – further TIPs on how to get the best user experience from this forum.

https://www.hornby.com/uk-en/forum/tips-on-using-the-forum/

.

[busman 25]

Hi there, I must apologise to forum members who answered this post for a typo error in my first post, the power supply that I wanted to use is actually 15 volts 6 amp output, the 16 volt in the post was a typo error.

My understanding is that the item that power is supplied to will only draw the amperage that it needs, so the over provision of amperage would not normally be a problem, however, a reply by Chrissaf to my original post set a chain of thought in motion, my DCC system has always struggled to operate more than one loco, even when new, I was so disapointed with it that at one point I seriously considered returning to analogue, but I had invested a serious amount of money, and given the analogue controller and power supply away,  I installed a DCC ring with lots of drop wires and just persevered, so I have never given any thought to the possibility that the original power supply could not be supplying the correct voltage or amperage, I just naturally asumed that 1 amp was insufficient for the layout, but after borrowing a power supply from a friend last night and powering my layout with it, I find the performance is much improved, I can operate two loco`s correctly, and it looks as if three could actually be possible, so now I seem to have got to the root of the problem, and I thank everyone for their time and replies to my post.

[Chrissaf]

Good to hear that a further diagnostic check using substitution indicates that the original supply is faulty. At least you now know what direction to go in.

.

The official Hornby P9300 4 Amp power supply really is the optimum replacement power supply for the eLink.