Photo: pinballphotos
  1. » Forum
  2. » Electro-Mechanical
  3. » EM Pinball Tech
  4. » Checking relay coils while connected?
(Topic ID: 228412)

Checking relay coils while connected?

By tobiasbp

5 years ago



Topic Stats

  • 6 posts
  • 3 Pinsiders participating
  • Latest reply 5 years ago by tobiasbp
  • No one calls this topic a favorite

You

Linked Games

  • Flush Maguinas / Mac Pinball, 1976
0
0
0
#1 5 years ago
OP
 
???

tobiasbp

Inactive member

DK Copenhagen

5y 7,900 44 3

I'm checking the resistance of all relay coils in a Flush with a multimeter before switching the machine on for the first time. Some of the coils read below 2 Ohm, while others (of the same type, they have labels read 13 Ohm). The coils where i measure low resistance all look good, so I'm wondering if there is a scenario where the resistance I'm measuring is not across the coils them selves, but a connection outside the coil? That is, is there a scenario were the (relay) coils can not be checked while connected to the circuit?

0
0
0
#2 5 years ago
 
MJS

schudel5

Pinside member

20y 166K 6,398 27

When the switches are all closed, to allow the relay to energize, you are measuring the path of least resistance. This may not be through the coil itself, but rather through the windings of the transformer.

I'd just turn it on and be ready to shut it off immediately if you see or smell something happen.

0
1
1
#3 5 years ago
 
BLY

MrBally

Pinside member

US Paradise, NV

12y 141K 13,936 22 1

Let me know which coil(s) you are seeing with this phenomena. I'll need to see a high quality scan of the schematic from (for example) Staples ($2) or Kinkos ($6) for the particular machine.

0
0
0
#4 5 years ago
OP
 
???

tobiasbp

Inactive member

DK Copenhagen

5y 7,900 44 3

Quoted from MrBally:

Let me know which coil(s) you are seeing with this phenomena. I'll need to see a high quality scan of the schematic from (for example) Staples ($2) or Kinkos ($6) for the particular machine.

I think you are asking about schematics for the machine. I'm not aware of any schematics for Flush . It's a spanish copy of Royal Flush , but the wiring does not appear to be the same.

0
0
0
#5 5 years ago
OP
 
???

tobiasbp

Inactive member

DK Copenhagen

5y 7,900 44 3

Quoted from schudel5:

When the switches are all closed, to allow the relay to energize, you are measuring the path of least resistance. This may not be through the coil itself, but rather through the windings of the transformer.

That must be it. All the coils look great.

Reply

Wanna join the discussion? Please sign in to reply to this topic.

Hey there! Welcome to Pinside!

Donate to Pinside

Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!

This page was printed from https://pinside.com/pinball/forum/topic/checking-relay-coils-while-connected and we tried optimising it for printing. Some page elements may have been deliberately hidden.

Scan the QR code on the left to jump to the URL this document was printed from.