Overwatch - Hardware - Daughter board installation
Many EQSS Overwatch kits contain interface daughter boards. Correct installation is critical to reliable performance.
The correct fitment of these interface daughter boards is crucial to the reliable operation of an Overwatch system. This Tech Doc is an addition to the instructions within the EQSS Overwatch Installation Manuals and is intended to highlight the importance of good preparation and correct PCB pad dressing. If the preparation was done poorly, the Overwatch simply will not function reliably.
Example of an EQSS Harness and Daughter Board
Steps:
First clean mechanically all solder joints where the EQSS Overwatch Daughter board spring pins will connect to the scissor control board. All glue/silicon/conformal coating must be removed to properly expose the solder joints.
Crucially, then the control board contact points must be cut back with electronics side cutters until they are flush.
Use a fine, sharp pair of angled side
cutters to trim down the PCB pin contact points.
Ensure the pins are cut flush with the PCB to allow the Overwatch daughter
board spring pins to make suitable and
secure contact.
Example below: sharp, flush - side cutter (Tsunoda TM-10)
The photos below should be used as a guideline to ensure reliability in the final assembly.
Below - All silicone has been removed around the solder point.
When all preparations have been completed for the attachment of the daughter board, the bolting down of the daughter board onto the scissor control board can be finalized.
To assemble - use whatever method is easiest for you, but DO NOT USE SUPER GLUE to hold down the spacers during assembly, as most likely it will also end up on the spring loaded pins - rendering them non usable. When all spacers and screws are mounted loosely in place, gently wriggle the daughter board until satisfactory seating of the daughter board spring pins is achieved. Then carefully and evenly complete the tightening of the screws. When all screws have been tightened (do not over tighten), carefully check that the spring pins are making good contact with the control box PCB. You may need to look at the spring loaded pins at a number of angles to visually validate good contact. A more definitive continuity test can be used if an ohm meter is available. You will be looking for a very low DC resistance (typically less than 1 Ohm).
An example of a properly mounted daughter board
Example of what not-to-do (Super Glue over the spring pins and over tightening)
Testing spring pin integrity and continuity
When the screws of daughter board have been tightened on the control board, the spring pins can be tested for continuity with the DC resistance meter function on a multimeter. The easiest method of completing this task is to trace to a convenient PCB track/solder joint on the control board where the spring pin will connect and then finding a convenient PCB track on the daughter board to which the spring pin is soldered. Then probe with the two multimeter lead tips to those chosen points. The multimeter should read less than one Ohm of DC resistance.
If no resistance is measured (open circuit) then the daughter board pin is most likely not making contact with the machine control board. Partially unscrew all of the daughter board mounting screws and re-position the board slightly to re-align the spring pins.
If a DC resistance higher than one Ohm is found, then partially unscrew all of the daughter board mounting screws and re-position the board slightly to re-align the spring pins.
Screw down the mounting screws again and re-test for continuity. If all of the spring loaded pins measure less than one Ohm, then the daughter board install is complete.
Daughter board contact pins must be aligned and making good electrical contact with the flush cut control board solder pads for the Overwatch to properly function
Related Articles
OverWatch - Hardware - Harnesses and Kit differences
At EQSS we build Overwatch kits for many machine brands and models. As most machine models are different from each other it should come as no surprise to our customers that at EQSS we build and market different kits to suit those different machines. ...OverWatch - General - What is EQSS Overwatch and how does it work?
Principle of Operation The OverWatch™ is an innovative system designed as a safety aid to the operator. The system does not replace operator training. The system works on the premise of detecting the operator’s position and movements, with respect to ...OverWatch - Installation - Active Signal Decoder Wiring Diagram
Some JLG models have been updated to use an active signal decoder in the loom for sensing the drive and elevate functions Affected models: JLG Mxx69LE JLG xx94RT JLG xxxMRT On page 22 of the Installation Manuals for each of these listed above models ...OverWatch - Installation - Genie RT Harness Soldering
As part of the kit installation process, the Overwatch Genie RT harness requires some soldering This Tech Doc was not written as a step by step installation guide, but rather further guidance whilst following the actual published pdf installation ...Overwatch - Faults - Not Passing Installation Tests (OEM lights)
Some EQSS Overwatch kits receive their control signals from scissor control box LED display circuits. Overwatch kits are engineered and adapted to reliably function as a safety cutout system. Various control signals (within the scissor control box) ...