Slant *        6        Forum
Home Home Home
The Place to Go for Slant Six Info!
Click here to help support the Slant Six Forum!
It is currently Tue Aug 16, 2022 11:32 pm

All times are UTC-07:00




Post new topic  Reply to topic  [ 4 posts ] 
Author Message
PostPosted: Sun Jul 25, 2021 9:53 pm 
Offline
EFI Slant 6

Joined: Mon May 26, 2014 4:02 pm
Posts: 353
Location: Vermont
Car Model: Slant Six M37
I don't have room for a mechanical fan, as that would be my first choice.

I like the simplicity of a relay, and the fact that they tend to be more economical.

Also, this fan may run more due to it being in a slow moving vehicle.. Cruise speed is 35-45 MPH on level ground or downhill.

I know next to nothing about PWM controllers, other than the have a soft start. Are they reliable enough to justify in a slow moving lumbering truck?

What are your thoughts, what do I need to ask myself to make a good decision here?


Top
   
PostPosted: Sun Jul 25, 2021 10:07 pm 
Offline
Supercharged

Joined: Thu May 12, 2005 11:50 pm
Posts: 6292
Location: So California
Car Model: 64 Plymouth Valiant
I use 2 lighting relays on my Toyota truck.

Simple and cheap.

They're in parallel for redundancy (just in case)

_________________
Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

8)


Top
   
PostPosted: Mon Jul 26, 2021 10:07 am 
Offline
EFI Slant 6

Joined: Mon May 26, 2014 4:02 pm
Posts: 353
Location: Vermont
Car Model: Slant Six M37
emsvitil wrote:
I use 2 lighting relays on my Toyota truck.

Simple and cheap.

They're in parallel for redundancy (just in case)


Thanks, that confirms for me what I was leaning towards.


Top
   
PostPosted: Sun Aug 29, 2021 11:17 pm 
Offline
TBI Slant 6

Joined: Sun Jul 16, 2006 9:17 pm
Posts: 221
Location: NW New Jersey
Car Model:
Older electric fans with the big bulky motors use brushed DC motors. Newer slim motor'd fans use BLDC (BrushLess DC) motors. BLCD motors require a controller to operate properly. Many incorporate the controller within the motor, so all you have to connect is power and ground. BLDC is way more efficient than the older brushed motors.

That said, brushed motors respond well to PWM control. BLDC usually does, but not always. If you are looking for "on when hot, off when not", then the relay approach is the simplest solution. The only advantage to PWM is the ability to vary speed. PWM would offer slow speed when only slightly over-warm, higher speed when a bit more over-warm, ... full speed when outright hot. This requires some sort of temperature sensing (Analog to Digital Converter, or ADC) for a processor-based controller, or something like a LM555 timer that varies PWM based on a voltage input from an analog temp sensor.

With all that said, are your goals any more sophisticated than simply "turn the dang fan on before I pop a head gasket"? If not, use the relay and a thermo-switch to activate it. If you want the superior control of PWM, let me know. I may be able to help.

_________________
Recognized by US Federal Courts as a Fuel Economy Expert!


Top
   
Display posts from previous:  Sort by  
Post new topic  Reply to topic  [ 4 posts ] 

All times are UTC-07:00


Who is online

Users browsing this forum: No registered users and 8 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Limited