Crown DC 300A series II from 110V to 240V

[Cone Motion]

Hello forum 🤞🏻

Ive bought a DC 300A II to power my 4435 monitors in a propper way.

So far i changed the Fuse for 240V (Buss MTH 5) as reqired in the Manual at Page 14

In Germany here we have 230V 50Hz

What shall i choose 230V or 240V?

Maybe someone can give me a step by step to wire Everything correctly.

see atached Photos


It would be great to get some hints 😊

…and yes i Know the thread about the 300A, the MK II looks a Bit different.

 

[Netlist]

Welcome to the forum.
240V. Over here we have peaks of 236V, not sure where you live but I propose you measure it.

Hugo

 

[Cone Motion]

Germany

 

[simon7000]

Wiring for 240 it will work even at 230. Wiring for 230 it may fail at 240.

Best is to actually measure your mains voltage a few different times of day.

A true RMS meter is not required to do the test. In fact a cheap meter that measures the peak voltage and scales to the RMS is a better choice for this test.

 

[Cone Motion]

Okay so i just have to Bridge C and D for 240V nothing else? Vortage here varies more into the + Direktion so 228-235V as i saw it some months before during a Long Time messurement.

 

[Netlist]

Okay so i just have to Bridge C and D for 240V nothing else?

If it was wired for 120V, yes.

Hugo

 

[Cone Motion]

Thank you so far!

so its confirmed what my electrican sayd about the diagramm 👌

You Know the german Sense for safety😂👍

 

[Cone Motion]

Oh oh i tryed it with the Bridge from C to D result is a burned fuse, i Hope nothing hapened to the Amp on his way overseas :/ i think i try a local Radio repair Shop next.

If i Knie What produces that malefunction i let you Know about it.

After the MTH5 Fuse flashed the IOCs started to light up 1-3 seconds later, also They dimmed down then for around 8-10 seconds.

Capacitors okay?

 

[Netlist]

Are you sure that A and F were wired correctly?

Hugo

 

[Cone Motion]

AD CF so 120V was the Factory Setting

 

[Netlist]

Thus, you have taken the two short orange wires out and connected one of them to CD?
Strange...

Hugo

 

[basreflex]

You should have one orange wire left over, unused, unconnected

 

[Cone Motion]

exactly what i did.

What can it be?

is it a good idea to do the 240V wirering and use the original Fuse?

 

[basreflex]

good chance you bought yourself a crown shortcircuit. time to check it with a variac and start at low voltages. check out the secondary rectifier bridges. etc..

 

[Netlist]

I suggest you bring it to a reputable tech with experience in these kind of amps, send it to Crown ($$$) or ask for a refund.
These are not the kind of amps a (sorry) inexperienced diy-er should try to fix.
And don't use the 10A fuse, you'll make it worse.
All this for your own safety 🙂

Hugo

 

[Cone Motion]

I Try the local Technican at monday 👌

 

[Cone Motion]

Okay good news, the local technican sayd it works on the Factory Voltage and EU Voltage using a stable transformer on his workbench, also at 240V wirering using the EU Power Socket. he sayd the Amp has a switch on pulse of around 2A Peak and the Sound comes imediatly After Switch on, is that normal so far?

Also he Sayd its possible that my 230V Socket maybe has some sort of failure in the Ground (Neutral) wire, i try em out them at other Sockets then.

 

[Cone Motion]

Okay, so far there was no Problem so far, the Amp works perfectly, the reason for the burned MTH5 in 240V wirering is the Switch on Impulse of around 2A, ive found a MTH 5 who acts Slower.

The Burned MTH5 in Fast Version is mostly present if you empty the capacitors like Switch off and let them run out, (See picture IOC Indicators) in this case the impulse is to high for the usual MTH5 Fuse.

It acts Safe yet and im happy, verry linear and near humm free amp, also IOC doesnt light up at highest Output Power 👍

Ill buy a 2nd one and use them as Monoblocks for each 4435 Monitor

Thanks to the Forum for the hints!

 

[basreflex]

As the name already mentions, the amplifiers are dc amps, intended for shakers and other industrial testing. for audio it is wise to add an input coupling cap to protect any dc on your drivers.