CM1a-D-12V Relays no longer available (fan, headlight, etc)

[dcarver]

Chasing an electrical issue on KrZy8.. Noticed only had one spare Mouser bought relay, cm1-D-12V. No biggie, get buy some more.

No Sir.

Obsolete part. Digi-Key, Allied, Mouser.. Apparently around March 2015 this model w/diode deceased.

OBTW, the -D- means with clamping diode (prevents induced voltages being applied to bikes electrical system when the coil de-energizes).

Noticed that model CM1a-R-12V is available. With resistor. Not diode. Should be OK. Ordered 5. Will report back.

That is all.

Just FYI.

..and - Mouser and Digi-Key have the same price for both the fan relay and the 'Brodie' relay. Both sites have similar checkout mechanisms. Would not be surprised at all if both sites are the same parent company..

For the record -

Fan relay part number -

• Mfr CM1A-R-12V
• Digi-Key - 255-3729-ND
• Price - 4.68 USD

Brodie ignition harness part number -

• Mfr CB1AH-12
• Digi-Key - 255-2082-ND
• Price - 6.82 USD

That's all I know.

 

[harper]

Don-

I believe that this TE Connectivity part may be equivalent:

V23074-A2001-A403

Mouser has them as well as onlinecomponents. They should be Micro ISO base, 1 form C contacts, 12VDC coil with diode.

Here's the data sheet:

https://www.te.com/commerce/DocumentDelivery/DDEController?Action=srchrtrv&DocNm=V23074-X0000-A001&DocType=DS&DocLang=EN

 

[dcarver]

I need someone smarter than myself.. how important is the diode as compared to a dissipating resistor?

..and Harper,

 

[harper]

A snubber diode almost completely prevents the voltage across a relay coil from reversing polarity when the current in the coil is interrupted (when the relay is turned off). Using a diode doesn't require any additional current to keep the relay energized. A damping resistor in the same place reduces the amplitude of the voltage reversal of a relay coil when it is turned off, but does not generally eliminate it. This comes with the cost of an additional current that is required to keep the relay energized. More damping requires more excitation current because the resistor value is smaller.

Does that relay I mentioned look like an equivalent to you? It looks like the CM1A-D-12V is a sealed 1 form A relay with 35A peak current. The TE Connectivity part I gave you was 1 form C 30A peak. The high current option is more appropriate but it still doesn't look sealed to me. The 1 form A high current version is V23074-H2005-A502, same data sheet. Sorry for the confusion.

 

[harper]

Don-

Note that I changed the TE part number again. The TE packages are not sealed like the Panasonic packages. I have not yet found a sealed equivalent. My guess is that having a sealed package with a damping resistor is more important than having an unsealed package with a diode snubber.

 

[Constant Mesh]

Easy enough to add a diode to the coil circuit. I've installed diodes on all relays I've added to my FJR.

A diode does delay the drop out of the relay a bit. For almost all applications that's not a problem.

 

[harper]

Adding a diode like you say is the best solution. That way you can buy a relay with or without the damping resistor. I've done this to lots of relays but not on a motorcycle. Where do you make the attachment? I usually do it on the socket if there is one but I don't know what the layout is like on the FJR.