MoTeC PDM30 - Manual (Page 11)

8 Installation
Slow operation can be achieved using the switch or using intermittent
operation to give a similar effect which avoids the need for a high current
switch.
The fast/slow switch and on/off relay must handle the wiper motor current
(typically 4 ampere). The control switches can be low current types since they
only connect to PDM inputs.
4. Direct Method
PDM
Park
Switch
Home
M
S
F
Input
Output 9
Control
Switches
The wiper unit can be wired directly to the PDM as long as it is only connected
to one output.
In this method the park switch is wired directly to a PDM input so the park
logic must be configured in the PDM.
This method requires the use of Output 9 which performs motor braking. The
PDM performs motor braking by momentarily shorting the output to ground
when the output turns off.
The PDM must be configured with the appropriate logic to perform on/off and
intermittent operation based on the state of the control switches.
Slow operation can be achieved using a switch between the fast and slow
windings as used in the other methods or intermittent operation can be used
to wipe less frequently.
The control switches can be low current types since they only connect to PDM
inputs.
5. Direct Method with Linked Channels
– PDM Version 2
Hardware
The PDM Version 2 hardware has additional functionality to simplify
windscreen wiper motor control.
This method requires the use of Output 9 which provides special wiper
functionality:
- Output 9 is isolated whenever the user nominated linked high speed
wiper output is turned on. This protects Output 9 from the high voltage
generated by the slow winding, and also prevents Output 9 from