Message:25869 In: TECH.GBR
From: G8MNYDate: Tue, 14 Jul 26 06:40:00 Z
Newsgroups: TECH.GBR
Subject: Maplin 13A Socket Mains Tester
Message-ID: <64894_GB7CIP>
Path: GB7RJJ|GB7OSW|GB7BED|GB7CIP
R:260714/0932Z 16660@GB7RJJ.#79.GBR.EURO LinBPQ6.0.25
R:260714/0644Z 44154@GB7OSW.#16.GBR.EU LinBPQ6.0.25
R:260714/0644Z 14282@GB7BED.#21.GBR.EU LinBPQ6.0.25
R:260714/0640Z @:GB7CIP.#32.GBR.EURO #:64894 [Caterham Surrey GBR]
From: G8MNY@GB7CIP.#32.GBR.EURO
To : TECH@GBR
By G8MNY (Updated Mar 20)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)
This is a 230V AC 3 neon plug in safety tester. It can only detect simple
wiring faults!
Inside there is 2 PCBs with the Neons (DS1-3) & 8 Rs.
LiveÄÄÄÂÄÄÄÂÄÄÄÄÄÂÄÄÄÂÄÄÄÄÄÂÄÄÄ¿
R1 DS1 R4 DS2 R7 DS3
56K (=) 82K (=) 68K (=) * * * Mains OK
ÀÄÄÄ´ ÀÄÄÄ´ ÀÄÄÄ´ * * . No Earth
R2 ³ ³ * . . Live or Neutral reverse
82K R5 ³ . * * No Neutral
NeutralÄÄÄÄ´ 68K ³ . . * Live or Earth reverse
R3 ³ ³ . . . No Live
33K ³ R8
ÃÄÄÄÄÄÄÄÄÄÙ 82K
R6 ³
33K ³
EarthÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ
I took mine apart after DS3 started to flicker & then went permently out!
On testing with an isolation transformer fed from a variac. I found all it
worked properly on 260V. For some reasion the attenuation differences in DS1 &
DS3 feed Rs seems to be wrong. Isolating the Rs they are all quite nominal &
swapping the neon around did not move the fault.
So I replaced R7 & R1 with 100Ks, and it all works correctly now all 3 neons
extinguish near 210V, & the various fault indication functions all tested OK.
See my tech bul, "Maplin Mains Meter 2000MU-UK"
Why don't U send an interesting bul?
73 De John, G8MNY @ GB7CIP
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