"The Great Debate" - Plug Top or just Plug?

[GeorgeCooke]

The 3a fuse is a habit from pat testing where rewirable plug tops on items <700w should have 3a fuses. Anything else 13a.

Plug tops are not rewireable, plugs are. You are not very bright are you?

But anyway that is rubbish. Many items below 700w have switch on surges that would instantly blow a 3 amp fuse. Anyone who decides on a fuse on the running load of an appliance is not very bright.

The fuse is to protect the cable not the appliance. As such a 13 amp fuse would be OK on most appliances, or in Europe the 16amp MCB feeding the circuit.

 

[Lucien Nunes]

The 3a fuse is a habit from pat testing where rewirable plug tops on items <700w should have 3a fuses.

And mandatory for old appliances (often table lamps) that have 0.5mm² cable fitted.

Only ever use 13a and 5a fuses in plug tops

Except presumably when you encounter one of said 0.5mm² cables.

 

[DPG]

George you are very condescending and you don't half generalise. You seem to think nobody is very bright except you. But yet you only seem to bang on about the same 2 topics (plugs and manufacturer's instructions). Surely with all your wisdom you should be offering advice on some of the tricky questions that get asked.

 

[GeorgeCooke]

Understood. I know there are some very bright sparks. But sadly not all.

 

[Dave OCD]

Bulbs have built in protection. Most of the rest of the world don't have fuses in plugs and don't come to harm.

I'd agree that years ago the reputable filament lamp manufacturers incorporated a means of 'fusing' in their products but when such lamps became out of favour due to energy consumption vs lumens the market was seemingly flooded with cheap far Eastern lamps - I'm not sure these had or have any inbuilt protection at all and it's the momentary 'dead short' that sometimes occurs as they fail which will blow the fuse or even 6a MCBs at the CU.
But apart from all that I'll continue to fit 3 amp fuses where I deem appropriate.
By the way George, with you being such a stickler for correct terminology I'm quite surprised at your cavalier use of the word 'bulbs' .

 

[Lucien Nunes]

This one will appeal to George. Today, I was getting incorrect counts on a timecode generator that is driven with biphase from an optical encoder. Scoped the biphase lines and they were all over the shop. Checked the +5V supply from the box to the encoder, there's 100Hz ripple on it which is mucking up the encoder operation.

It's an American unit, which I am powering from the 230V mains here in Estonia, via a step-down autotransformer. Hmm, I thought, maybe my step-down is giving too low a voltage for the unit, causing the DC rail to drop out of regulation. Let's see what the supply voltage is, and what it is supposed to be.

Transformer output rating: 110V. Actual: 115V
TCG rated operating voltage: 115V

So, no, nothing to do with 110V vs. 115V vs. 120V. Actually, a bona fide failed capacitor in the power supply. It's working now.

 

[Jim_e_Jib]

This one will appeal to George. Today, I was getting incorrect counts on a timecode generator that is driven with biphase from an optical encoder. Scoped the biphase lines and they were all over the shop. Checked the +5V supply from the box to the encoder, there's 100Hz ripple on it which is mucking up the encoder operation.

It's an American unit, which I am powering from the 230V mains here in Estonia, via a step-down autotransformer. Hmm, I thought, maybe my step-down is giving too low a voltage for the unit, causing the DC rail to drop out of regulation. Let's see what the supply voltage is, and what it is supposed to be.

Transformer output rating: 110V. Actual: 115V
TCG rated operating voltage: 115V

So, no, nothing to do with 110V vs. 115V vs. 120V. Actually, a bona fide failed capacitor in the power supply. It's working now.

It appeals to me too but not for voltage related reasons - what equipment were you working on? We have a lovely Rank Cintel MKIII telecine that kicks out biphase to sync to an Albrecht MB51 sound follower.

 

[Midwest]

This one will appeal to George. Today, I was getting incorrect counts on a timecode generator that is driven with biphase from an optical encoder. Scoped the biphase lines and they were all over the shop. Checked the +5V supply from the box to the encoder, there's 100Hz ripple on it which is mucking up the encoder operation.

It's an American unit, which I am powering from the 230V mains here in Estonia, via a step-down autotransformer. Hmm, I thought, maybe my step-down is giving too low a voltage for the unit, causing the DC rail to drop out of regulation. Let's see what the supply voltage is, and what it is supposed to be.

Transformer output rating: 110V. Actual: 115V
TCG rated operating voltage: 115V

So, no, nothing to do with 110V vs. 115V vs. 120V. Actually, a bona fide failed capacitor in the power supply. It's working now.

Sorry Lucien, for once your talking total -------s. Here's a better explanation;

 

[Midwest]

How? There is nowhere to put a fuse in the top.

There's a little set of tinned or brassy contacts in the plug top where the fuse goes. If you like I can draw you some pictures to explain. Anybody got some crayons?

 

[GeorgeCooke]

There's a little set of tinned or brassy contacts in the plug top where the fuse goes. If you like I can draw you some pictures to explain. Anybody got some crayons?

You'll find they are in the plug bottom. Dare I say it? You are not very bright are you?

 

[Midwest]

You'll find they are in the plug bottom. Dare I say it? You are not very bright are you?

Don’t be daft, there ain’t such a thing as a plug bottom, thicky.

 

[GeorgeCooke]

Don’t be daft, there ain’t such a thing as a plug bottom, thicky.

Dare I say it? You are not very bright are you?

 

[telectrix]

ther is a plug top and a plug bottom. it's the bottom that holds the terminals and the top that keeps fingers out. in it's entirity, it's a plug.

 

[Spoon]

ther is a plug top and a plug bottom. it's the bottom that holds the terminals and the top that keeps fingers out. in it's entirity, it's a plug.

Would you class the bit that holds the cable the 'plug middle'... or am I just being thick again....??

 

[Pete999]

Would you class the bit that holds the cable the 'plug middle'... or am I just being thick again....??

You and Tel uping your post count again, I see, LOL

 

[Spoon]

You and Tel uping your post count again, I see, LOL

I like to contribute to these fascinating discussions mate...

 

[telectrix]

if you plugged a plug into a cheesecake, would it affect the circuit IR readings?

 

[Spoon]

if you plugged a plug into a cheesecake, would it affect the circuit IR readings?

You are the one with the meter, mate. Give it a try....
Send any leftover cheesecake to me....

 

[telectrix]

the answer is no, because the cheesecake is not part of the circuit.

 

[Pete999]

I like to contribute to these fascinating discussions mate...

Right I get you,