I found this last year and thought some of you could find this helpful.
Posted by Pounder on Nov 29th, 2011
Today I will be reviewing the PolarStar (P*) Fire Control Unit (FCU). It will be more of a walk around then a review. I will be going over the settings, what they mean and how that correlates to BB’s going downrange. I have been “Polarized” for about three months now and have had an absolute blast with my Fusion Engine (FE). This will just be about the FCU and I will cover the rest of the P* FE system in other reviews. Also Please do enjoy the pictures we have taken.
Basically the FCU is a small computer that controls the timing of a few different things on a P* FE. It is very simple and is quite user friendly. It has a small joystick on the board and it can be clicked in and also clicked up, down, left or right. Here is an excerpt stoled from the P* FE instructions.
“To enter programming mode, press inward on the programming button. The display will show “SAFE” indicating the trigger is disabled and the system is in programming mode. Press the programming button again to exit programming mode. Setting changes are automatically saved upon exiting.
While in programming mode the various settings may be accessed by pushing the programming button left or right. The values are changed by pushing the button up or down.
The Fusion Engine FCU may be returned to the factory defaults by holding in the programming button while plugging in the power supply.”
It is as simple as that to change the settings. The best part if you mess it up then all you have to do is reset it. When you reset the FCU the readout will show “dEFT”. I have seen that some people really don’t want to mess with the settings. There really is nothing you can break from adjusting some things. You can make the replica not feed right and not fire but just reset it and then go at it again.
One thing to remember is that all the values add up in time. So the higher the overall time the slower the cycle rate will be. The lower the time the faster the cycle rate will be. Some of the settings need to be near the default values so that the system will feed and shoot accurately.
So now we are going to get down to the nuts and bolts of it. When you first go into programming mode you will see “re11”. This is just the revision of the FCU. It can not be adjusted. Next up is:
-This one is super simple. Full Auto and Full. Basically this is where you get to burst mode. You can set your burst between 1-9 or have full auto. Burst of 1 you ask? The reason for this is so if you need to run a DMR in semi only this will basically work as a lockout for that. There are couple other ways to do this but they will be covered in a later review. I personally run a three round burst. It is efficient on a midcap but you can just pull the trigger rapidly and basically have a fully automatic fire rate. Default value on this is FU. No not you, the FCU!
-This a pretty slick setting that will help mags feed or you can increase the rate of fire through it. Dn stands for Nozzle Dwell. Basically this determines how long the air nozzle stays at the rearward position. So if you have a mag that does not like to feed very quickly then raise the numbers slowly till it does. If your mag feeds well then feel free to lower it to up the rate of fire. Default value for this is 12.
-This setting is how long your system will blow. haha Well hopefully it doesnt blow. DP stands for Poppet Dwell. Basically this controls how long air is allowed to flow out of the air nozzle and down the barrel. For the auto guys out there, think pulse width. This may not seem super important but this setting is IMHO the most important value you can adjust. This is what separates the Fusion Engine from an AEG. Since you can throw a larger volume of air down the barrel you can continue to accelerate the BB all the way to the end of the barrel. This setting will be different for different length barrels, different inner diameter barrels, hopup units, hopup buckings, and also different weight and brand of BB’s. We have found that even at lower velocities (<350fps) that we can effectively hop and produce range with a .40 Bioval BB. Typically this will be too heavy for most AEG’s especially at that FPS. But you turn up the dP and then you are able to really put a lot of air behind the BB. I would say go up from the default (20) rather then down. Yes you are adding time to the total cycle but this is where the range and accuracy really come in.
This is one of those things that affects how the replica feeds but you will not necessarily get much as far as performance gains from it. You can work the number lower and this will increase the rate of fire but too low and it will not feed properly. Default value is 22.
This is one of the fun ones. It is ROF delay. So basically it sets up how much time between shots on full auto. It may just be me but I crank it all the way to 1. This is the lowest time between shots. We have found that with extensive tuning that the accuracy and range will drop off with a very high rate of fire (35-40+/sec). To achieve this you have to play around with a few other setting to reduce the cycle time as well. If dn and dr are at default then I would say crank it to one. If you want to play with the other settings then this can be adjusted up or down to make it shoot the way you want. Another aspect of this is if you want a strict milsim you can adjust your replica to shoot similar to what the actual weapon would shoot. You can also set it higher to reduce rate of fire which will be more efficient on BB usage. Default value is set at 12.
This one I have never had to touch. It is there to filter out electricial noise on the trigger switch. So the higher the number the longer the trigger must be held before it will read it as a trigger pull. Default setting is 00.
Closed bolt mode is really slick when you run semi auto. Basically if Cb is off then the system will cycle then shoot. With Cb on it will shoot then cycle. We have an indoor arena locally and I love Cb on for there. They only allow semi so it increases the trigger response and also gives me the drop over AEG’s that have to cycle before they shoot. Default is set to of (off). You can also experiment with closed bolt vs open bolt to achieve different BB flight characteristics and accuracy. Don’t be afraid to experiment!
Feel free to play around with the settings. Also a .40g BB is getting to be a little too light with this system so if you are not running at least a .30g BB then you are not even getting close to maximising the potential of the system. We are now running into limitations with the industry not creating heavy enough BBs for us PolarStar users. I will be doing other P* reviews in the near future so stay tuned for some other ways to optomize your P*.