User guide
SENSORRAIL IIIE  8200-0593-03, REV. A 
SERVICE GUIDE
22 of 34 
Power Supply Modification and 
Adjustment
WARNING! Unplug the power cord to the 
PowerRail module to ensure there is no 
power to the rail. 
1.  Using the template below to determine the hole 
location, drill a 10mm hole in the PowerRail 
module to gain access to the adjustment screw. 
•  About 5mm up the drill bit, wrap tape 
approximately 10 times around the bit to stop 
it so it does not go too deep into the 
enclosure. 
•  Grease the bit or use a vacuum close to the 
bit while drilling to prevent metal filings from 
getting into the enclosure. 
2. After drilling, clean filings from the area. 
3.  Reconnect wires and turn on the PowerRail 
module. The trolley should perform its power-up 
routine. 
4.  Using a voltmeter set to dc (Track 1 = voltage, 
Track 2 = Gnd), connect its probes to the 
contacts shown below. Then using a small 
screwdriver, adjust the potentiometer to 27Vdc 
maximum. 
5.  Test the trolley’s motion to the furthest point and 
back. 
Note: Because the PowerRail module RS-422 
output is not tri-state, additional devices cannot 
be daisy-chained or parallel-wired to the rail. 
Instead, connect the rail to separate channels on 
an RS-422 system, or use an RS-422 junction 
box. 
The PowerRail module is shown below with the 
new access hole. Note plastic screws and thick 
washer in plastic used to isolate the power 
supply from the rail. This prevents multiple 
ground paths if you have RF video issues. 
12mm 
28mm 
10mm dia. hole to access 
the power supply 
adjustment potentiometer 










