CP Miniscan HPE's

[Jamtastic3]

Hi all,

Ok so I have 4 CP Miniscan HPE's that I've been working with for 2 years now. I used someone else's scans and noticed that their main fan (the big one out of the 2) was sucking into the unit (to the lamp). On mine the fan sucks outwards like the small fan next to it.

Now does this mean after 2 years, my fans have been put in wrong?

I phoned Clay Paky and all they said that as long as you can't see the label from the outside then that's the way it should be (so the big one should be sucking inwards). I disagree with this becuase I tried this and the units overheat more, but now I'm just confused. If anyone else knows these lights well it would be great to share your advice.

[woody74]

I want to believe they should be exhaust fans, so at the very least, you are not sucking smoke and dirt into your heads.

[Brian]

I want to believe they should be exhaust fans, so at the very least, you are not sucking smoke and dirt into your heads.

But if they suck out of the unit then the rubbish will still get in through the air inlets.

[niclights]

It is an exhaust fan. It should suck out.

 

As for smoke/dirt you introduce in either direction!

[DJ Dicky]

correct design practice says you should always blow air into a unit for cooling as sucking hot ait over the fan dries out the lubrication in the bearing causing premature fan failure.

 

Don't know which way your units were designed for though

 

Dicky

[Jamtastic3]

Ok here's a quick understanding....

On the underside (we're talking scans here) there's 2 fans next to one another - one large one just below the HMI lamp and one small one just under the main electronics. On the top side of the unit there is a 'grill' that has no fan. Some light output spills from this but not much as there is a small metal 'lip' covering the lamp.

 

Now my theory is this... the small and big fans exhale the air from the unit and this cools it down down more compared to if the big fan was inhaling because there is a certain amount of air flow force created from the lip of the lamp cover and the grill, forcing the air through from the one grill and out through two fans.

If the large fan was inhaling and the small fan is exhaling then although there is a circulation of air happening, the grill stops any air flow from happening.

 

phew... hope I haven't confused things more!

[niclights]

I am 100% sure that both should exhaust. Small fan exhausts air from ballast. Large fan exhausts air from lamp. The large fan does die on a regular basis almost certainly because of the lamp heat, but I think if you reversed the airflow you would have much bigger problems. You are probably right that if one was intake and one was exhaust then the heat would not be correctly removed from the lamp (top) side.

[Fender Bender]

Both fans should exhaust ( blow air) out of the bottom of the scan. There are arrows on the sides of the fans showing airflow direction.

[woody74]

I want to believe they should be exhaust fans, so at the very least, you are not sucking smoke and dirt into your heads.

But if they suck out of the unit then the rubbish will still get in through the air inlets.

 

Well, yes, of course. But his comment was the large fan by the lamp, so I guess I should have been more clear: I wouldn't want to suck smoke directly onto my lamps.

 

-w

[Jamtastic3]

Both fans should exhaust ( blow air) out of the bottom of the scan. There are arrows on the sides of the fans showing airflow direction.

 

Yes but that's just telling you the direction, so you could place it as an exhaust or the opposite. The arrows would have to be on the unit to show what way it should be.

 

Thanks for the advice guys. I'm asking all this because it's got to a point where I'm at breaking point, arguing with the lighting engineer whos fan are in different. You know it's not great when 2 engineers are working against one another and not with one another!

[Fender Bender]

Jamtastic3 Posted Today, 5:00 AM

Yes but that's just telling you the direction, so you could place it as an exhaust or the opposite. The arrows would have to be on the unit to show what way it should be.

 

I'll try again, Both Fans exhaust out of the BOTTOM !!!!! thats how they all come from the factory

the other guy is wrong!

if you do the Scan training course they will tell you the same thing.

If you have ever had to buy a spare small fan from CP it's supplied with a rectifier/regulator card attached. (this mod was added about 6 years ago) it now only fits 1 way guess what --- the the arrow points toward the bottom.

 

Hope this helps.

[niclights]

Yup, absolutely! I've been servicing them for last 8 years. Is the rectifier/regulator card only specific to the small fan? I have only just ordered one for a unit that sounds like there will be a problem, but the fan has nothing like this. What is its purpose?

[Fender Bender]

It only applies to the small fan. it's a 12v dc fan originally supplied from the 12v dc rail. the mod means the fan is now supplied from the ac side of the psu, then rectified at the fan. ( I think this was done to prevent a fan fault affecting the main dc supply). this does not apply to the large fan as it is a 240v ac unit.

 

All the spares I've got from cp/pulsar thru AC lighting since the mod, have been supplied with the board fitted. I brought 6 last month.

Did you spare fan come from cp/pulsar?

[Jamtastic3]

When we get ours serviced, we get them done by a major entertainment company in Edinburgh and they have been placing both the small and big fans as exhausts. I service them myself to save money just by cleanng them out once an month, but now I know how to change the fans - its just the direction thing that's getting me (well spilling into an argument with another LD)

[niclights]

@Fender Bender: Tnx for that. All my parts are sourced thru' AC. I will have a closer look tomorrow. Cheers :D