How to get to the inside of the hpl7780 to connect the multi-wire planar cable from the control panel.

You will need to take the side panels off to get to the circuit boards. The Main board is often on the right hand side when looking from the front

Yes, the control board may be bad . Ihave attached a procedure for checking the hall effect sensors, some of which you will not have the special tool needed to preform all the tests. However it will allow you to check the control board which may be bad causing your problem.

VSD FAULT DIAGNOSTIC GUIDE
10 Revision 001 - March, 2002
Appendix 4 - Hall Effect Sensor Checks (Four Part)
1. Isolate the compressor from the main incoming voltage supply. Lock and tag the
isolation switch in the open position.
2. Allow 15 minutes for the VSD to discharge capacitors.
3. Open enclosure doors to expose the VSD.
4. Check with a suitable meter that all voltages have dissipated before beginning work on
the VSD.
5. Remove rear cover of drive motor to permit rotating by hand.
TEST 1
6. Disconnect Hall Effect Cable from P4 on the Control Board, plug type is DB9 Type.
7. Inspect cable pins and matching receptacle connections for damage or bent pins.
Remove cover of plug and inspect solder connection of the wires for damage.
9. Inspect entire length of the cable for damage. If cable and connections are in good condition,
proceed to Test 2.
TEST 2
9. Confirm supply voltage to the Hall Effect Sensor is present using a digital multi-meter.
10. Disconnect terminal strips P1, P2 & P3 from the bottom of Control Board.
11. Trip and switch off MCB2 and MCB5 to prevent the SGN Intellisys from powering up.
12. Re-connect main incoming supply voltage to the unit. Isolation contactor KM1 should remain
de-energized and the VSD should only receive control power. Caution must be taken as the
panel has voltage present.
13. Set digital multi-meter to DC Volts.
14. Connect Black probe of multi-meter to either of the 2 pins of P16.
Note: P16 is located on the Control Board, slightly less than half way down and towards the left side.
P16 is marked and described as 2 small bare pins. P16 is the ground connection for the Control
Board.
15. Locate the small transistor just above Pin 3 on terminal strip P1. The transistor has 3 pins on
the left side. The pins are numbered 1 at the top, 2 in the middle and 3 at the bottom.
16. Connect Red probe of multi-meter to Pin 3. The voltage should be between +11 and +14 Volts
DC.
17. If voltage is not present, replace the Control Board.
VSD FAULT DIAGNOSTIC GUIDE
11 Revision 001 - March, 2002
TEST 3
17. Connect special adapter XXXXXXXX between P4 on the Control Board and the Hall
Effect Sensor Cable.
19. Set digital multi-meter to DC Volts.
20. Connect Black probe of multi-meter to either of the 2 pins on P16.
21. Connect Red probe of multi-meter to Red wire of the adapter. Rotate motor by hand and
observe measurement. The meter should read between +10 and +12 Volts DC.
22. Repeat the test with the Black wire of the adapter. The meter should read between +10 and +12
Volts DC.
23. Repeat the test with the Yellow wire of the adapter. The meter should read between +10 and +12
Volts DC.
24. If voltage does not rise to between +10 and +12 Volts DC for any of the 3 sensors, replace the
Hall Effect Sensor Assembly.
TEST 4
25. Set digital multi-meter to Ohms.
25. Connect multi-meter between Purple and Green wires of special adapter XXXXXXXX. The meter
should show a resistance value of approximately 150 Ohms ± 20% (New Hall Effect Sensors)* at
70° F (20° C) ambient temperature.
27. If correct value is not confirmed, replace the Hall Effect Sensor Assembly.
Note: Two temperature ranges (130° C and 150° C) of Hall Effect Sensor have been used. Typically,
the 50/60hp (37/45kW) units use a 130° C sensor and the 75/100hp (55/75kW) units use a 150°C
sensor. All sensors have a small band near the sensor end of the cable.
The 130° C sensor has four digits such as 6622 on the band. The 150° C sensor could have either a
four digit number with a star on each side (*6752*) or a four digit number followed by a star and the
letter E (6752*E) or a four digit number followed by an E (7652E).
Appendix 5 - Megger Main Motor Windings
1

If only one color is not working - it is usually just the connector of the screen or the monitor cable itself that is faulty. Remove the Monitor Data cable that plugs into your PC and check that NO pins are bent or pushed into the socket - then re-insert the VGA connector into the PC and make sure that the part of the cable that plugs into the monitor itself is also secured properly. That should solve the problem. If not - it could be the cable itself - bend the cable at the connector to check for a lose wire inside. If the color suddenly comes back - replace the data cable to the monitor.

Hope this helps
Good Luck

Navigate to the control panel, click Start then click control panel.

Double click power options.

On the Power Schemes tab ensure that the fields are set to NEVER.

You can however set the monitor to turn off after 20min which I do recommend, to make your computer more energy efficient.

damnor01

It is not reset problem, more likely to have failure inside the monitor.
Most common failures in the LCD monitors are bad capacitors (bulging top/seal or leaking) in the power supply, failed inverter circuits (blown fuse, shorted transistors, shorted/open transformers), bad lamps (poor solder connections or worn out lamps). You will need to open it up and inspect the inside, see example of failed monitors to get some ideas what to look for: http://s807.photobucket.com/home/budm/allalbums
Post back what you see inside so we can guide you further and it will help out other people in the future also.
http://en.wikipedia.org/wiki/Capacitor_plague
http://www.badcaps.net

in this model there is a problem with wifi connection, hp has just released its patch, connect the printer with usb cable and then donwload the patch from hp.com/support and then run the patch, it will find the printer and it will update the firmwar of printer, and i asure u that then it will start working fine,i have resolve this problem alot, i am from hp itself. :)

Make sure you video cable from the computer is seated in correctly.

Email this guy @ [email protected], he has planar parts to sell.

ebay!

www.Ebay.com =)