6
Mechanical Fixing
The PP420 can be mounted onto a flat surface using the mounting holes in the corners, see
diagram. The PP420 should only be mounted either vertically or with its base horizontal. It
should be mounted at least 15mm away from the sides of plastic enclosures. Likewise leave a
similar space between the PP420 and any parts which could be affected by high temperatures.
The enclosure of the PP420 is used to dissipate power in the form of heat. See the
section on Heat Dissipation.
The PP420 can be mounted from above using the corner holes, or from beneath using the M4
tapped holes (maximum screw length inside is 6mm).
The PP701 kit is available for mounting the PP420 on a DIN rail.
To avoid a fire hazard consider the implications of overheating in the unlikely event of a
fault in the PP420. The power dissipation in a fault condition is approximately given by
the sum of the following for the four channels:
(<Power supply voltage> - <rated voltage for lighting>) * <max current delivered by Power supply>
Either limit the power supply output current(s) so that not more than 30W can be dissipated in
the PP420, or mount the unit in an enclosure.
To limit the power, set the power supply output voltages to the minimum value required by the
LED light and the PP420 together. Chose a PSU that limits its output current by design, by