8 replies to this topic

[haleymon]

Does anyone know the specs of the AC power adapter for CPC scopes.

It is most likely 12 Volts but what are the Amps/Milliamps for it.

I have a box of 12 VAC adapters with different amp ratings and would hate to buy someting I already have.

Thank

[Greg K.]

12 VDC, 1.5A.

The connector is 2.1mm inside diameter, 5.5mm outside diameter, tip positive. Don't use a 2.5mm inside diameter, as it'll be too loose and give you nothing but problems.

[Digital Don]

Apparently Celestron will be bringing one out: Celestron AC adapter

It's 2.5 amps which is more than enough to run the CPC scopes. Doesn't seem to be available yet though.

Don:usa:

[kx9i]

That's right. I just preordered the new Celestron AC power cord from Optcorp. It should ship later this month.

[New Mexico Craig]

A word of caution : I ordered the "Celestron AC adaptor" for CPC scopes from Starizona for my CPC 1100. After much 'not in stock' delay they finally shipped it to me on 21 May 08.

Their website advertises it as the 2.5 amp Celestron adaptor. Which is completely untrue.

Bogus AC adaptor

Not only is the adaptor they sent me not Celestron (it's Tamuracorp), it is also clearly printed right on the adaptor that it's only 1 amp.

Caveat emptor.

craig

[Digital Don]

The part number for the actual Celestron 2.5 amp adapter is 18778 (see the link above). It is apparently not yet available.

Craig, I hope you were able to return the 'bogus' unit to Starizona at their expense.

Don:usa:

[rookie]

Last year this forum had discussions about power adapters for the Nexstar and CPC scopes. The moderator at that time, RandyR, had his scope develop electronic problems with varying current from his ac adapter during a utility power surge. He frequently cautioned people from using anything but a regulated power adapter, like the ones used for a laptop computer. A stand alone battery is still the safest. The lightening capital of the America's, maybe the world, is the Interstate 4 corridor in Florida. I won't connect my scope to ac power here. !@#$%

The ac adapters for the first generation CPC scopes were unregulated. I'm hoping Celestron has improved the design. Do you know if these new power adapters have regulators?

[Greg K.]

Yep, I remember that discussion - it's good advice, better to err on the side of caution.

I always hook up via battery (Coleman Powermate 18 Amp/hour). It's a lot more convenient than AC power anyway. The only way I'd go with a power supply is if I had a permanent observatory.

[mclewis1]

The issue was (is) the difference between cheaper "wall wart" style power supplies, better quality power supplies and batteries.

The Celestron supplied 12v supply for the NexStar11 GPS scopes was a nasty little 1.5amp unit that wasn't built very robustly. The failure of some of the components caused the supply to loose it's regulation, putting out a fairly high raw voltage. It was this supply that failed and cooked RandyR's scope.

Celestron then released a 2.5amp unit, this time with a slightly better design and components. This supply has now been discontinued ... presumably to be replaced with the model now seen on the Celestron website. I believe that Starizona has some website problems with the description of the discontinued Celestron unit and the picture of a newer 1amp unit.

These are the power supplies that Celestron made available in North America ... there were/are different unit used in other geographic locations.

There are a ton of other "wall wart" supplies around, most are of a simple design and built from very cheap components. Using one of these is basically a *BLEEP* shoot, it's highly unlikely to have a problem but still statistically more likely than better quality units or batteries alone. The primary problem with any of them is heat. The sealed design and limited amperage capacity usually leads to a lot of heat build up within these units. Heat is the number one enemy of any type of power supply.

One of the other alternatives are better quality power supplies, one example of which are the brick style units. These tend to have pretty good regulation and overvoltage protection designs. The brick style package also tends to offer good cooling characteristics. A specific example is the Pyramid PS-9KX (12v 5amps).

- The "wall wart" style supplies tend to be under $25 and already have the appropriate power plug (2.1mm x 5.5mm).
- The brick style units start at about $25 and usually need an appropriate cable to connect to the scope/mount (another $15-20 ... or much less if you make your own).
- Batteries start at around $50, and higher capacity units around $100. Good quality deep cycle units with capacities to handle much more than just the scope can go from $250 to whatever. Batteries are indeed the safest option but will initially cost more and will need to be replaced after a few years of heavy use.