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Electronics => Repair => Topic started by: Yamin on November 08, 2018, 04:17:32 am

Title: Hameg HM1008 Scope
Post by: Yamin on November 08, 2018, 04:17:32 am
Hi, I have got 4 units of Hameg HM1008 all with the same capacitor blown on the power supply. Has anyone else come across this problem?What could be the possible reason - all the units are maybe 6 years old. I haven't removed the pcb yet so don't know the function of the cap for sure but I'm assuming it used to filter out the main AC in.
Can you please help me to identify the make of this capacitor
Thanks in advance
Title: Re: Hameg HM1008 Scope
Post by: tautech on November 08, 2018, 04:42:20 am
Hi, I have got 4 units of Hameg HM1008 all with the same capacitor blown on the power supply. Has anyone else come across this problem?What could be the possible reason - all the units are maybe 6 years old. I haven't removed the pcb yet so don't know the function of the cap for sure but I'm assuming it used to filter out the main AC in.
Can you please help me to identify the make of this capacitor
Thanks in advance
Yep, exactly that.
They're one of the X or Y class of caps and not necessary for operation.
Replace with non-translucent case varieties.
Title: Re: Hameg HM1008 Scope
Post by: coromonadalix on November 08, 2018, 09:59:48 am
The capacitor is in the line filter section  before the bridge rectifier, if i recall this capacitor can crack on the casing and fail ?
Title: Re: Hameg HM1008 Scope
Post by: Glare on November 17, 2022, 09:32:45 pm
This is a WIMA MP 3-X2. Try a comparable MKP-X- or Y-type as a replacement. From a safety perspective, however, the MP-types would be more favorable.
Title: Re: Hameg HM1008 Scope
Post by: Hamelec on November 18, 2022, 08:00:57 am
a well known issue of these RIFA caps / exploders..
change it erverywhere you will find it.
Title: Re: Hameg HM1008 Scope
Post by: George Edmonds on November 18, 2022, 10:06:05 am
Hi

Please note,  X an Y capacitors are NOT interchangeable.

X capacitors should ONLY be used phase to neutral or phase to phase, NEVER to Earth / Ground / or whatever it is called where you are.

Y capacitors can be used phase or neutral to Earth / Ground / or whatever it is called where you are.

The reason for this is one of safety, Y capacitors MUST fail open circuit to avoid any possibility of making the equipment case live following a failure, whereas X capacitors need not fail open.

G Edmonds