Summary
It has been reported by in field technicians that some Kill Switches have failed in the field. When set to kill, the engine can potentially start. This puts the operator of the equipment at potential risk of severe injury. This bulletin is therefore required to be circulated to all people working on Controllis generators.
Directive For Site Engineers and/or operators
For all persons working in the field, the Kill Switch is no longer a specific point of isolation before working on the units. For activities that are non-invasive, either mechanically or electrically, such as refueling there may be no concern and a risk assessment should be carried out with reference to local regulations.
Temporary Site Work Around
In order for units to be worked on safely, in the short term, it is critical that the unit is isolated prior to starting. There various methods to choose from in order to achieve this, but the recommended method is set out below. The operator / engineer should select the method that they are most comfortable with after performing any appropriate assessment of risks with reference to any additional equipment on site.
the recommended method of disabling the starter is by disconnecting the start circuit. This can be done by removing cable 576 from the start relay in the panel. This cable is accessible as it is at the top of the relay and is also pre-insulated to prevent any electrical shorts. The photo below shows the numbered cable.
Once removed, the set can be worked on as this runs directly to he starter motor and when disconnected no power can be switched to energize the start solenoid.
Retrofit For Long Term
In order to make the site safe, it is essential that the time is taken to fix the issue for the safety of everyone. it is most appropriate that on the first site visit this work is undertaken. The recommended fix is below, which can be done with minimal materials on site.
General Principal of Retrofit
The idea of this retrofit is to remove the current kill switch cabling and connect them together (to remove the current kill switch circuit). And to then connect the starter relay output and fuel relay output back through the kill switch, so when the kill switch is off, the start circuit is open and the engine is unable to start.
Tools
In order to carry out the fix you will need the following materials and standard electrical tools in addition to any normal tools and equipment for site access.
A set of Allen Keys
A 13mm Spanner
Pre-insulated cable crimpers
Wire Cutters
Flat screwdriver
Materials
An additional contact block for the kill switch (https://cpc.farnell.com/raas/rb2-be101-bp/22mm-switches-n-o-block/dp/SW03551?CMP=TREML007-005)
4mm Cable (or 6mm Cable), Two lengths 24cm, Two Lengths 46cm long
2 x 6.3mm Yellow pre insulated spade terminal (male) (A)
2 x 6.3mm Yellow pre insulated spare terminal (female) (B)
4 x 3.5mm Yellow pre insulated fork terminal (C)
1 x Blue pre insulated blue through connector terminal (D)
3-4 100mm cable ties
Instructions
Strip all 8 cable ends.
On the two short cables fix an (A) on one end and (C) on the other.
On the long cable fix (B) on one end and (C) on the other
These are all the cables made up.
Using the Allen key on the socket cap screw and 13mm spanner on the nut that holds the Kill Switch, remove it from the side of the control panel case. Fit the additional terminal block to the rear of the kill switch.
With the flat head screwdriver, undo the terminals on the Kill Switch to release the cables. There is a single cable in one side with a pre-insulated terminal and group of 3 cables in the other side, again with a pre-insulated terminal. Cut the terminals off the single cable, strip the cable end and crimp it into one side of (D). Then cut the three cables, strip each end and put all three into the other side of (D). The current kill switch circuit is now linked together and disabled.
Now remove cable 576 as per image below from the start relay and put the male spade terminal from the short cable you have premade above into this female spade terminal.
The take the long cable and put the female spade terminal onto the start relay. The put the other ends of these cables with the 3.5mm forks into one of the kill switch terminal block.
The control panel after doing the start relay will now look like this (without the cable ties fitted so its easier to see).
Now repeat this process, but do it to the fuel relay. Cable number
Reconnect the Kill switch to the control panel case.
Fix the two cables to the existing loom with the cable ties.
You should then verify and test the kill switch works as expected before signing off the retrofit.
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