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chara:trouble_shooting [2022/01/18 22:47] charaobs |
chara:trouble_shooting [2022/01/21 17:55] charaobs |
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You may have to reinitialize the scope on a bright star. If the powers were turned off quickly when the problem was noticed, the position of the scope should be retained and slewing to a bright star will get it in the finder. If not, you may need to go out to the telescope to find the bright star to reacquire the scopes position. | You may have to reinitialize the scope on a bright star. If the powers were turned off quickly when the problem was noticed, the position of the scope should be retained and slewing to a bright star will get it in the finder. If not, you may need to go out to the telescope to find the bright star to reacquire the scopes position. | ||
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- | ==== Telescope clock is not correct ==== | ||
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- | The NTP server has obsoleted this problem and fix as of 2014. | ||
==== Telescope is not receiving the commanded position for a target ==== | ==== Telescope is not receiving the commanded position for a target ==== | ||
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==== Telescope is tracking poorly, overshooting in slew, oscillating. ==== | ==== Telescope is tracking poorly, overshooting in slew, oscillating. ==== | ||
- | This might mean that the gain for the tracking servo is wrong. Note that changing this gain can be dangerous, especially if you set it too high as that can cause the telescope to oscillated and damage the drives. Please only do this if you are very very sure that it is necessary. Symptoms of bad gain are: The scope over shoots the position while slewing. The star will be seen to move out of the window and may come back after a few seconds. This means the slewing gain is too low. The scope oscillates when tracking or after a slew. The star will be tracing an ellipse, figure eight or other looping shape. This means the tracking gain is too low. You can damp this out with the telescope or dome gui by disabling the scope, then re-enabling it. Adjust the gain upward and watch it on the next slew. In all cases if either gain is too high the scope will go into "Fog Horn" mode, which is bad. You always want to use the lowest gain that still allows the scope to work as best as possible. If the tiptilt tells you the scope is oscillating slowly, the gain may be too low. If it is oscillating quickly it may be too high. On 10-22-2016, the gain settings were: | + | This might mean that the gain for the tracking servo is wrong. Note that changing this gain can be dangerous, especially if you set it too high as that can cause the telescope to oscillated and damage the drives. Please only do this if you are very very sure that it is necessary. Symptoms of bad gain are: The scope over shoots the position while slewing. The star will be seen to move out of the window and may come back after a few seconds. This means the slewing gain is too low. The scope oscillates when tracking or after a slew. The star will be tracing an ellipse, figure eight or other looping shape. This means the tracking gain is too low. You can damp this out with the telescope or dome gui by disabling the scope, then re-enabling it. Adjust the gain upward and watch it on the next slew. In all cases if either gain is too high the scope will go into "Fog Horn" mode, which is bad. This can be seen during slews on the twfs or labao as vibrating spots, usually in one axis. |
- | |Scope|AZ Slewing| |AZ Slewing| |AZ Tracking| |EL Tracking| |Date Updated| | + | You always want to use the lowest gain that still allows the scope to work as best as possible. If the tiptilt tells you the scope is oscillating slowly, the gain may be too low. If it is oscillating quickly it may be too high. |
- | | |Gain|Fn|Gain|Fn|Gain|Fn|Gain|Fn| | | + | |
- | |S1|7|4|4|3|16|4|10|7|10-26-2017| | + | |
- | |S2|7| |7| |10| |10| |10-22-2016| | + | |
- | |E1|7| |7| |13| |10| |10-22-2016| | + | |
- | |E2|7| |7| |13| |10| |10-22-2016| | + | |
- | |W1|13| |10| |13| |10| |10-22-2016| | + | |
- | |W2|7| |7| |13| |13| |10-22-2016| | + | |
- | \\ | + | The usual values for slewing gains are 4-7 and tracking gains are 7-10. Note that these values may change as the temperatures change rapidly. |
- | Note that these values may change as the temperatures change rapidly. | + | |
==== How to Adjust CPUMotor Gains ==== | ==== How to Adjust CPUMotor Gains ==== | ||
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* Good metrology signals are important to the proper positioning of the carts. Monitor the signal strength by running [RUN MULTIPLE] on the Metrology Monitor. Place the windows above the TV windows for each scope you are using. They should show white sine waves that are around the height of the window. Erratic, fluctuating waves indicate self-interference or a weak signal. This may cause the carts to lose their place as the signal strength falls too low. Red waves indicate that some displayed signal has gone too low and the carts will all need to be homed. A careful adjustment of the MET2 mirror can sometimes bring the signal back. Do not adjust the MET1 mirror. | * Good metrology signals are important to the proper positioning of the carts. Monitor the signal strength by running [RUN MULTIPLE] on the Metrology Monitor. Place the windows above the TV windows for each scope you are using. They should show white sine waves that are around the height of the window. Erratic, fluctuating waves indicate self-interference or a weak signal. This may cause the carts to lose their place as the signal strength falls too low. Red waves indicate that some displayed signal has gone too low and the carts will all need to be homed. A careful adjustment of the MET2 mirror can sometimes bring the signal back. Do not adjust the MET1 mirror. | ||
- | * To home the carts, turn off the [OL] and [MAN] buttons on each cart and it will automatically return to the front switch. If the cart has no issue, it will arrive at the target position of 0m and the home switch at the same time. The X in the OPLE server under the HM will indicate it has stopped on the home switch. If a cart does not reach the home switch when it returns to position 0m, it was lost and likely the cause of the difficulty in finding fringes. The X does not guarantee the cart has retained its home position. This can only be done by using the CHECK button on the ople gui or by typing the command " | + | * To home the carts, turn off the [OL] and [MAN] buttons on each cart and it will automatically return to the front switch. If the cart has no issue, it will arrive at the target position of 0m and the home switch at the same time. The X in the OPLE server under the HM will indicate it has stopped on the home switch. If a cart does not reach the home switch when it returns to position 0m, it was lost and likely the cause of the difficulty in finding fringes. The X does not guarantee the cart has retained its home position. This home position |
===== Beam Samplers ===== | ===== Beam Samplers ===== |