Hi All

I have a Graco paint sprayer and cutting a long story short am thinking of converting it to corded.

I have looked online and it seems at least for drills this seems doable however the ones I have seen so far have the batteries which push on to the drill and have 2 connections. The paint sprayer has an 18v slide on type lithium ion battery with many connections and the sprayer has 3 connectors to the battery.

Anyone ever tried doing this before? A few initial questions spring to mind
1. I can clearly identify the + and - but what is the 3rd one for and what should I connect it to? I have temporarily wired the + & - to a DeWalt battery + & - and it seems to work.

2. The sprayer says it is 15 amp so assume I need a transformer whose output power is at least 270 Watts ? I have seen these

https://www.amazon.co.uk/Regulated-S.../dp/B01N9BDX6I

As an example so assume something like this would work?

3. I was thinking of striping out the cells from the existing battery and wiring just the 3 connectors the sprayer uses to the transformer. I assume the rest can be left disconnected?

4. Maybe a daft question but presumably any wire I use has to be able to handle 15 amps (or if I go for the 360 watt one I might as well ensure 20 amps)? Is the fact that it is 18v DC important when selecting the cable? Eg is normal cable design for 20 amps at 240 v AC correct?

5. Any suggestions on the connectors to use? Was going to do a split in the cable so that in the future I could add other battery types of needed to the same rig. Was planning on soldering connectors in the battery itself (assume any electrical solder is ok?) And assume the transformer will come with connectors to connect to it.

Any top tips etc or bitter experience of doing this would be greatly appreciated

Thanks

Lee.

It happens that formulated :
4. Maybe a daft question but presumably any wire I use has to be able to
handle 15 amps (or if I go for the 360 watt one I might as well ensure 20
amps)? Is the fact that it is 18v DC important when selecting the cable? Eg
is normal cable design for 20 amps at 240 v AC correct?

20amps DC requires the same cable as 20amp AC. 240v cable will need to
be more robustly insulated than that for 18v.

Powering it from a power supply will possibly make it a bit unweildy to
use. A 240v version will probably be better.

On 07/10/2018 10:58, Harry Bloomfield wrote:
It happens that formulated :
4. Maybe a daft question but presumably any wire I use has to be able
to handle 15 amps (or if I go for the 360 watt one I might as well
ensure 20 amps)? Is the fact that it is 18v DC important when
selecting the cable? Eg is normal cable design for 20 amps at 240 v AC
correct?

20amps DC requires the same cable as 20amp AC. 240v cable will need to
be more robustly insulated than that for 18v.

I might suggest volt-drop becomes the overriding consideration.

Powering it from a power supply will possibly make it a bit unweildy to
use. A 240v version will probably be better.

Fredxx formulated the question :
I might suggest volt-drop becomes the overriding consideration.

Yes, good point, if the cable between the two is going to be longer
than a few feet.

On Sunday, 7 October 2018 10:49:26 UTC+1, wrote:
Hi All

I have a Graco paint sprayer and cutting a long story short am thinking of converting it to corded.

I have looked online and it seems at least for drills this seems doable however the ones I have seen so far have the batteries which push on to the drill and have 2 connections. The paint sprayer has an 18v slide on type lithium ion battery with many connections and the sprayer has 3 connectors to the battery.

Anyone ever tried doing this before? A few initial questions spring to mind
1. I can clearly identify the + and - but what is the 3rd one for and what should I connect it to? I have temporarily wired the + & - to a DeWalt battery + & - and it seems to work.

2 connections are fine, the 3rd monitors battery temp.


2. The sprayer says it is 15 amp so assume I need a transformer whose output power is at least 270 Watts ? I have seen these

that's a gamble

https://www.amazon.co.uk/Regulated-S.../dp/B01N9BDX6I

As an example so assume something like this would work?

another gamble. Many such can only sustain a quarter of rated output


3. I was thinking of striping out the cells from the existing battery and wiring just the 3 connectors the sprayer uses to the transformer. I assume the rest can be left disconnected?

yes, they're for charging

4. Maybe a daft question but presumably any wire I use has to be able to handle 15 amps

yup

(or if I go for the 360 watt one I might as well ensure 20 amps)? Is the fact that it is 18v DC important when selecting the cable? Eg is normal cable design for 20 amps at 240 v AC correct?

mains flex has 2 layers of thicker insulation. You don't need that

5. Any suggestions on the connectors to use?

I thought you already had the battery casing

Was going to do a split in the cable so that in the future I could add other battery types of needed to the same rig. Was planning on soldering connectors in the battery itself (assume any electrical solder is ok?) And assume the transformer will come with connectors to connect to it.

?
What you want's a power supply, not a transformer

Any top tips etc or bitter experience of doing this would be greatly appreciated

Thanks

Lee.

12v tools are easier


NT

Thanks all for you advice. Much appreciated. I didn't quite follow the comments about insulation. Is normal 240v 20amp certified cable ok? In terms of the voltage drop issue, is there a type of wire which would make a noticeable difference? I would have thought I would need about 3 or 4m of cable to enable ceilings to be sprayed etc.

Yes I plan to use the battery casing and solder the cable to the connectors inside (using normal electrical solder?). The connector I was referring to was to split the cable between power supply and battery casing to enable me to use the supply for other battery types.

wrote on 07/10/2018 :
Thanks all for you advice. Much appreciated. I didn't quite follow the
comments about insulation. Is normal 240v 20amp certified cable ok? In terms
of the voltage drop issue, is there a type of wire which would make a
noticeable difference? I would have thought I would need about 3 or 4m of
cable to enable ceilings to be sprayed etc.

Without knowing the actual current it normally draws and the starting
current, it is impossible the answer. 20amp rated cable for 15amp load,
ought to take care of both load and volts drop.

A decent power supply rated for that, will be expensive. You need to be
looking at what is called a 'switched mode power supply' - a normal
transformer type will be quite a heavy lump to carry around.

The lower the voltage, the higher the current for the same wattage. The
higher the current the more voltage is dropped due to cable resistance.
The lower the voltage the more voltage drop becomes a factor.

On Sunday, 7 October 2018 11:35:30 UTC+1, wrote:
Thanks all for you advice. Much appreciated. I didn't quite follow the comments about insulation. Is normal 240v 20amp certified cable ok?

sure, it just has excess pvc

In terms of the voltage drop issue, is there a type of wire which would make a noticeable difference? I would have thought I would need about 3 or 4m of cable to enable ceilings to be sprayed etc.

1.5mm2 has 44mV drop /m /1.5A. At 20A that's 0.586V. No big deal for the sprayer, but it's 10W for the cable. Pick something fatter.


Yes I plan to use the battery casing and solder the cable to the connectors inside (using normal electrical solder?). The connector I was referring to was to split the cable between power supply and battery casing to enable me to use the supply for other battery types.

anything rated for 20A and not in use for something else is good.


NT

On Sunday, 7 October 2018 12:52:52 UTC+1, wrote:
On Sunday, 7 October 2018 11:35:30 UTC+1, wrote:

In terms of the voltage drop issue, is there a type of wire which would make a noticeable difference? I would have thought I would need about 3 or 4m of cable to enable ceilings to be sprayed etc.

1.5mm2 has 44mV drop /m /1.5A. At 20A that's 0.586V. No big deal for the sprayer, but it's 10W for the cable. Pick something fatter.

oops
x4m = 2.34v & 40W, no good at all.
2.5mm^2 - 1.4v no
4mm^2 - 0.875v 17.5W no good...


NT

On 07/10/2018 11:10, Harry Bloomfield wrote:
Fredxx formulated the question :
I might suggest volt-drop becomes the overriding consideration.

Yes, good point, if the cable between the two is going to be longer than
a few feet.

With a supply as cumbersome as listed then it probably needs to be left
on the ground when spraying. Also, the battery is a sealed power source
whereas the power supply is only designed for a indoor and clean
environment and it may react badly to being over-sprayed with whatever
substance is in the gun.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

formulated on Sunday :
oops
x4m = 2.34v & 40W, no good at all.
2.5mm^2 - 1.4v no
4mm^2 - 0.875v 17.5W no good...

You (and the OP) may be confusing start current, with the run current.
It cannot be drawing anywhere near 15amps when running, or the
batteries would obviously last no time at all. Call the battery
3amp/hour 15amp load = 12 minutes run time.

alan_m formulated the question :
With a supply as cumbersome as listed then it probably needs to be left on
the ground when spraying. Also, the battery is a sealed power source whereas
the power supply is only designed for a indoor and clean environment and it
may react badly to being over-sprayed with whatever substance is in the gun.

The SMPSU need be no bigger, heavier, or cumbersome than a typical
desktop PC PSU. About the size of a brick, weighing maybe 0.5 Kg.

On Sunday, 7 October 2018 13:14:08 UTC+1, Harry Bloomfield wrote:
tabbypurr formulated on Sunday :

oops
x4m = 2.34v & 40W, no good at all.
2.5mm^2 - 1.4v no
4mm^2 - 0.875v 17.5W no good...

You (and the OP) may be confusing start current, with the run current.
It cannot be drawing anywhere near 15amps when running, or the
batteries would obviously last no time at all. Call the battery
3amp/hour 15amp load = 12 minutes run time.

I hadn't calculated it. If the OP knows the run time & battery capacity he can calculate apx run current.

PSUs vary in their overcurrent ie start current behaviour. Many shut down, meaning the compressor would never get going. On old fashioned supplies that could be fixed with a sufficiently huge capacitor. What a random smps would make of that I don't know.


NT

On Sunday, 7 October 2018 10:49:26 UTC+1, wrote:

I have a Graco paint sprayer and cutting a long story short am thinking of converting it to corded.


4. Maybe a daft question but presumably any wire I use has to be able to handle 15 amps (or if I go for the 360 watt one I might as well ensure 20 amps)? Is the fact that it is 18v DC important when selecting the cable? Eg is normal cable design for 20 amps at 240 v AC correct?

Electrically, and in the absence of faults, thinner insulation would suffice. But the insulation must also defend the wire from the external environment, and for that one must consider that it might be crossing a gravel path and get trodden on by football boots, it might be considered food-like by the local rabbits and squirrels, etc.

If the sprayer has exposed or exposable metal parts, all such need to be either double-insulated from 230-volt-land or reliably earthed.

Remember Lord Finchley.

--
(c) Dr. S. Lartius, UK. Gmail: dr.s.lartius@ |

On 07/10/18 10:49, wrote:
Is the fact that it is 18v DC important when selecting the cable?

Yes

Eg is normal cable design for 20 amps at 240 v AC correct?

No. To drop 5 v at 240v 20A is no big deal. To drop it at 18V is.
Use car style wires or specalist wires made for model cars/planes etc.



--
Its easier to fool people than to convince them that they have been fooled.
Mark Twain

On 07/10/18 11:05, Fredxx wrote:
On 07/10/2018 10:58, Harry Bloomfield wrote:
It happens that formulated :
4. Maybe a daft question but presumably any wire I use has to be able
to handle 15 amps (or if I go for the 360 watt one I might as well
ensure 20 amps)? Is the fact that it is 18v DC important when
selecting the cable? Eg is normal cable design for 20 amps at 240 v
AC correct?

20amps DC requires the same cable as 20amp AC. 240v cable will need to
be more robustly insulated than that for 18v.

I might suggest volt-drop becomes the overriding consideration.

+10001


Powering it from a power supply will possibly make it a bit unweildy
to use. A 240v version will probably be better.





--
Of what good are dead warriors? €¦ Warriors are those who desire battle
more than peace. Those who seek battle despite peace. Those who thump
their spears on the ground and talk of honor. Those who leap high the
battle dance and dream of glory €¦ The good of dead warriors, Mother, is
that they are dead.
Sheri S Tepper: The Awakeners.

On 07/10/2018 11:35, wrote:
Thanks all for you advice. Much appreciated. I didn't quite follow the comments about insulation. Is normal 240v 20amp certified cable ok? In terms of the voltage drop issue, is there a type of wire which would make a noticeable difference? I would have thought I would need about 3 or 4m of cable to enable ceilings to be sprayed etc.

Yes I plan to use the battery casing and solder the cable to the connectors inside (using normal electrical solder?). The connector I was referring to was to split the cable between power supply and battery casing to enable me to use the supply for other battery types.

https://www.ebay.co.uk/itm/14-AWG-5-...AOSwOdpXx6K c

Two-core silicone? this one only comes in a five foot length but 1) it's
nice and flexible and 2) it will deal with the voltage drop problem.

Single core is readily available in various gauges and decent lengths.
You could bind two together with that spiral polythene stuff but then
you would lose much of the flexibility advantage.

In article ,
wrote:
If the sprayer has exposed or exposable metal parts, all such need to be
either double-insulated from 230-volt-land or reliably earthed.

Not if run from a suitable low volts supply.

--
*Aim Low, Reach Your Goals, Avoid Disappointment *

Dave Plowman London SW
To e-mail, change noise into sound.

On Monday, 8 October 2018 10:53:47 UTC+1, Dave Plowman (News) wrote:
In article ,
wrote:

If the sprayer has exposed or exposable metal parts, all such need to be
either double-insulated from 230-volt-land or reliably earthed.

Not if run from a suitable low volts supply.

no, it's the psu that those apply to


NT

On 07/10/2018 11:35, wrote:

Thanks all for you advice. Much appreciated. I didn't quite follow
the comments about insulation. Is normal 240v 20amp certified cable
ok? In terms of the voltage drop issue, is there a type of wire which
would make a noticeable difference? I would have thought I would need
about 3 or 4m of cable to enable ceilings to be sprayed etc.

The cable typically used on DC tools is a high flexibility rubber
insulated flex, with quite substantial cross section - the cores usually
2.5mm^2 or in some cases 4.00mm^2.

Yes I plan to use the battery casing and solder the cable to the
connectors inside (using normal electrical solder?). The connector I
was referring to was to split the cable between power supply and
battery casing to enable me to use the supply for other battery
types.

On my Mirka sander, they have used a locking Neutrik connector like:

https://www.neutrik.com/en/products/power

It works very well, easy to connect or disconnect, not too bulky, and
locks in place when in use.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In article ,
John Rumm wrote:
On my Mirka sander, they have used a locking Neutrik connector like:

https://www.neutrik.com/en/products/power

Big fan of those. They seem more robust than any other mains (etc)
connector I've come across.

--
*One nice thing about egotists: they don't talk about other people.

Dave Plowman London SW
To e-mail, change noise into sound.

On 08/10/2018 14:29, John Rumm wrote:

The cable typically used on DC tools is a high flexibility rubber
insulated flex, with quite substantial cross section - the cores usually
2.5mm^2 or in some cases 4.00mm^2.


4m of the latter will weigh about a kilo? That's not a lot, but it might
be noticeable spraying the ceiling for a long time?

On 08/10/2018 14:55, GB wrote:
On 08/10/2018 14:29, John Rumm wrote:

The cable typically used on DC tools is a high flexibility rubber
insulated flex, with quite substantial cross section - the cores
usually 2.5mm^2 or in some cases 4.00mm^2.


4m of the latter will weigh about a kilo? That's not a lot, but it might
be noticeable spraying the ceiling for a long time?

You can always clip the cable to your belt, so you are only "carrying"
half the length of the bit from belt to tool. Also you will have lost
the weight of the LiIon battery, so should not be significantly worse
off than before.

The cable on my sander is about 4m long, and while its fairly heavy, you
don't really notice it because of its great flexibility and because the
machine itself feels quite "dense" in the hand even if in absolute terms
its very small and light.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Dave Plowman wrote:

wrote:

If the sprayer has exposed or exposable metal parts, all such need to be
either double-insulated from 230-volt-land or reliably earthed.

Not if run from a suitable low volts supply.

I've seen some Graco battery-powered sprayers that *do* need an earth to
prevent static buildup when used with the "wrong" type of paint ...

https://youtu.be/Xlf9dzOBFvU