Calling Power Functions experts

[Ape Fight]

I'm building a large scale (heavy) MOC powered by PF.

It currently has;

1 x Medium motor (Steering),

2 x XL motors (Drive),

1 x IR Receiver, and

1 x Battery Box

The IR Receiver apparently has an overload function that cuts power to the motor if there is too much strain. This means sometimes you can't steer and drive at the same time.

What is the best way of curing this? Is it 2 x Battery Boxes and 2 x IR Receivers, each set to the same frequency but one doing the 'Blue' functions and one doing the 'Red' (which seems a bit weird not using the duel functionality)?

Also how much load can a battery box take? Mine is currently powering 3 motors, but I may upgrade to 5 (2 x additonal XL motors). I'm conscious I don't want the battery boxes, if I fit more than 1, powering a different no. of motors if some of those are drive motors - as the batteries will not deplete evenly and eventually some drive motors will be 'carried' by others.

Hope that all makes sense - help gratefully received!!

[RockeTeK]

I don´t know if a receiver has an overload function, but that seems weird to me.

If you decide to use two receivers, you should use (in this case) two controllers aswell.

Create two separate setups of battery box, receiver, motor, controller.

If possible, try two battery boxes on the XL motors. (so you get 3 boxes in total)

Normally only one battery box is enough, but since your model will be (extremely) heavy...

Hope this helps

Edited February 27, 2011 by RockeTeK

[JopieK]

well have a look at our beloved philohome site about PF:

http://www.philohome.com/pf/pf.htm

Those PF XL motors draw quite some current so... But the reason that you can't have both IR outputs running at the same time is the format of the IR messages from the controller (the remote I mean). If you would use the train controller that wouldn't be a problem I think.

[DLuders]

There are LOTS of Lego Technic Power Functions (PF) vehicles out there that run 2 ea. PF XL motors and one PF Medium motor off of ONE battery box and TWO receivers.

From the LEGO.com Power Functions Frequently-Asked Questions (FAQs) webpage:

Question 2: "How many Power Functions Motors can I drive from one Power Functions Battery Box?"

Answer -- "As a rule of thumb, you can drive 2 Power Functions XL-Motors, 3 Power Functions Train Motors or 4 Power Functions M-Motors at the same time from one Power Functions Battery Box. If you wish to run a combination of motors, you can e.g. have 1 XL and 2 M running together. The XL-Motor requires about twice as much power as the M-Motor. The Battery Boxes and the IR Receiver have overload protection, so attempting to drive too many motors will not damage anything. The power a motor consumes depends on what function the motor is performing. Motors will operate best when driving a small load."

Question 12: "What happens when the Power Functions overload protection kicks in?"

Answer -- "Overload protection is activated when too much power is consumed from either a Power Functions Battery Box or the IR Receiver. This can happen when a motor is blocked or when too many motors are running at the same time. If overload protection is activated, the Battery Box or the IR Receiver will cut off power to the output until power consumption has dropped under the allowed value. To regain power, unblock the motor or disconnect motors from the output – then turn the Battery Box OFF and ON again. Under overload protection, the green light on the Power Functions Battery Box will still be ON."

[DLuders]

@ Ape Fight: By chance, is the "large scale (heavy) MOC powered by PF" this 85-studs-long x 26-studs-wide truck? You left too many clues on MOCpages:

Edited February 27, 2011 by DLuders

[Ape Fight]

@ Ape Fight: By chance, is the "large scale (heavy) MOC powered by PF" this 85-studs-long x 26-studs-wide truck? You left too many clues on MOCpages:

Yup! It's not too far off done now too : ) But I'm fiddling about with the power as it just keeps getting heavier and heavier!

P.S don't recognise your name here, do you go by anything else on MOCpages / Flickr?

[allanp]

I would think one XL motor is enough to drive that MOC.

[Ape Fight]

I would think one XL motor is enough to drive that MOC.

So did I. Originally it had one XL in the chassis and a free load area / workshop. Now it has two stacked XLs, with room for another two. It's also geared down twice from small to large cogs. I.e: heavy!

[Alasdair Ryan]

what is it that you are biulding? am useing one xl for my skip truck

Edited February 27, 2011 by Alasdair Ryan

[Ape Fight]

what is it that you are biulding? am useing one xl for my skip truck

See the above pics that someone's posted ^^

[Alasdair Ryan]

what i ment was what type of vechile is it bus,carvan,truck?

[DLuders]

From Wikipedia:

"The Fiat 682 is the first real truck versatile trucks and tractor trailers, manufactured by Italian automaker Fiat VI from 1952 to 1988. It is part of the vast family of heavy trucks Fiat VI equipped cabin. This vehicle will be manufactured for over 36 years and will be the main means of transport still currently serving in Africa. It covers the range heavy transport 16 to 44 tons."

[Alasdair Ryan]

thanks DLuders

Edited March 1, 2011 by Alasdair Ryan

[Ape Fight]

thanks DLuders

Hi Alasdair - in this case it's a 1959 FIAT 682 rebodied by Bartoletti for Scuderia Ferrari (in short their race car transporter) : )

You can check out the finished model soon on MOCpages

Good luck with your truck!

Edited March 1, 2011 by Ape Fight

[DLuders]

On his Flickr photostream, Ape_Fight posted 17 pictures of his completed Fiat 682/RN2 Bartoletti. He wrote that it has "Full Power Functions remote control, opening doors, dropping tailgate, lowering top deck, detailed interior."