Open/Close is not working
Last updated on:
21 Jul 2008
Make sure that both the Rotation Controller and the Shutter Controller PWR LEDs are illuminated.
Make sure that the SHUTTER DIP switch is OFF for the Rotation Controller, and ON for the Shutter Controller. Make sure the FACTORY DIP switch is OFF for both controllers. (Cycle the power if you change a setting.)
Try the manual open/close switch on the Shutter Controller. If the manual switch works but the computer commands do not, check the magnetic induction "antenna" on both controllers. The LINK LEDs on both the Rotation Controller and Shutter Controller should both be "warbling" twice (with a slight pause in-between) every two seconds. If not, check the induction "antenna" wires. At least one must loop fully around the observatory; otherwise the shutters may not work in certain dome positions. The other loop can be a shorter, but at least three feet long and at least one foot high. If a short loop is used, it must be located with the long side parallel to the other wire, as close to the other wire as possible. Try to avoid placing the loops in direct contact with ferromagnetic metals like carbon steel, as this might affect the magnetic fields. If you have insufficient signal and are using a short loop on one side, try making the loop longer and wider, or switch to a long loop around the whole dome.
If the manual open/close switch does not work, then check the limit switch LEDs. If the shutters are both closed, the CLS and HOME LEDs should be lit. If they are both open, then the OPEN and ROT LEDs should be lit. If the shutters are at an in-between position, the LEDs should be off. If the LEDs are in the wrong state, then the limit switch problem may be preventing any motor operations.
Open the ASCOM Dome Control Panel. Go to the Dome setup, and set "Report Partially Open As" to "Open Shutter". Connect the link. If the status shows Shutter Error, then the link between the Rotation Controller and Shutter Controller is not working. Check the induction antenna wires, and also check for any local sources of electromagnetic interference. Try turning off other devices to see if they are interfering with the link. (Be sure to restore the setting once this test is complete.)
Interference from other devices is extremely rare. The range of these signals is very limited, and very few devices use these frequencies. A continuously blinking LINK light may indicate interference from another device. Since the communications distance inside the dome is very short, a simple solution to interference may be to reduce the sensitivity of the wire loop. To do this, place a small resistor in series with the wire. The correct value may be determined by trial-and-error: large enough to remove the interference, but small enough to allow communications within the dome.
As of the time of writing, only the FriendlyRobotics® RoboMower is known to potentially cause interference, if the perimeter wire is directly adjacent to the observatory. To prevent interference, either locate the perimeter wire away from the observatory, or turn off the "perimeter switch" during observatory operation.
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