Display Window
Display During Normal Operation
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| Illustration 1 | g00732300 |
Display window of the oil mist detector (1) Fault number (2) Percentage of opacity (3) "Alarm" LED (4) "Test" LED (5) "Ready" LED (6) "Alarm Level" switch | |
Immediately after electrical power is supplied to the oil mist detector, the detector determines a baseline for the opacity. Approximately 30 seconds are required for the self-adjustment. LED number 1 flashes during this phase.
For the 191-6505 Oil Mist Detector and the 149-5143 Oil Mist Detector, normal operation is indicated by the following display:
- The percent of change in the opacity of the oil mist in comparison to the basic opacity is indicated. To determine the percent, refer to the numbers under "%" symbol (2). If the opacity is between two levels, the light will fluctuate between the indicators.
- The alarm relay is switched OFF and red "Alarm" led (3) is OFF.
- "Test" LED (4) is OFF.
- The ready relay is switched ON and green "Ready" LED (5) is ON continuously.
Note: During normal operation, the light may fluctuate between the numbered indicators ("%") in order to indicate that the opacity is between two levels. Be sure not to confuse this indication with a fault condition. During normal operation, the green "Ready" LED is ON. During a fault condition, the green "Ready" LED is OFF. Refer to "Display for a Fault in the Detector".
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| Illustration 2 | g00732415 |
Numbers and indicators for the valves of the 149-5143 Oil Mist Detector | |
In addition to the above display, the valves for the 149-5143 Oil Mist Detector are open. The valves are indicated by numbers that correspond to colored indicators in the valve box. The 191-6505 Oil Mist Detector does not have this feature.
Display for an Alarm for Excessive Oil Mist
191-6505 Oil Mist Detector
If the opacity of the oil mist becomes greater than the setpoint for the alarm, the condition is indicated by the following display:
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| Illustration 3 | g00732437 |
"Alarm" LED | |
- The alarm relay is ON and the red "Alarm" LED is flashing.
- The ready relay is ON and the green "Ready" LED is on continuously.
- The display continues to indicate the opacity ("%").
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| Illustration 4 | g00732475 |
"RESET" button | |
To reset the detector after an alarm condition, press the "Reset" button.
149-5143 Oil Mist Detector
If the opacity of the oil mist increases to a level of ten percent of the setpoint for the alarm, this detector operates in a pattern that searches. The valves in the valve box are activated according to a defined sequence. The opacity of the atmosphere from each compartment is sampled individually. This determines the compartment that has an increase of oil mist.
If the opacity of the oil mist becomes greater than the setpoint for the alarm, the alarm condition is indicated by the following display:
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| Illustration 5 | g00732437 |
"Alarm" LED | |
- The alarm relay is ON and the red "Alarm" LED is flashing.
- The ready relay is ON and the green "Ready" LED is on continuously.
- The display continues to indicate the opacity ("%").
- A red indicator in the valve box indicates the compartment with the greatest opacity. The compartment is identified by a number that corresponds to the red indicator.
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| Illustration 6 | g00732415 |
Numbers and indicators for the valves of the 149-5143 Oil Mist Detector | |
To reset the detector after an alarm condition, press the "Reset" button.
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| Illustration 7 | g00732475 |
"RESET" button | |
Display for a Fault in the Detector
For information on troubleshooting the fault conditions, see the Testing and Adjusting, "Troubleshooting" topic.
| NOTICE |
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If a fault condition occurs, the alarm relay for oil mist detection is switched OFF. During a fault condition, the oil mist cannot initiate an engine shutdown for excessive oil mist. If a fault condition occurs, correct the condition as soon as possible. |
The detector is capable of self-diagnosis for several fault conditions. If a fault condition occurs, the LED that corresponds to the condition will be flashing. The fault condition is identified by a number to the left of the LED. The conditions are listed in Table 1.
| Identification of the LED and the Corresponding Fault Condition | |
| LED | Condition |
| 14 | The pressure of the vacuum in the measuring head is too low. |
| 13 | An infrared filter is dirty. |
| 12 | Spare indicator |
| 11 | The ambient temperature is less than 1 °C (33 °F). |
| 10 | The ambient temperature is greater than 70 °C (158 °F). |
| 9 | The temperature of the electronic module is less than 1 °C (33 °F). |
| 8 | The temperature of the electronic module is greater than 75 °C (167 °F). |
| 7 | The reset button is faulty. |
| 6 | Spare indicator |
| 5 | The "Alarm Level" switch is faulty. |
| 4 | The measuring track is faulty. |
| 3 | The flashing of these two indicates that the electronic module is faulty. |
| 2 | |
| 1 | This indicator flashes for approximately 30 seconds immediately after power is supplied to the detector. |
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| Illustration 8 | g00732488 |
Example of the display for a number 14 fault condition | |
A fault condition is indicated by the following display:
- The red LED that is dedicated to the fault flashes.
- The alarm relay is switched OFF and the red "Alarm" LED is OFF.
- The ready relay is switched OFF and the green "Ready" LED is OFF.
- The "Test" LED is switched OFF.
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| Illustration 9 | g00732475 |
"RESET" button | |
In addition to the display, the "RESET" button can be pressed in order to display the opacity. To determine the opacity of the oil mist during a fault condition, press the "RESET" button. The red flashing LED will be extinguished and the LED that corresponds to the opacity will light continuously. If the "RESET" button is pressed again, the red LED that corresponds to the fault will flash again.
Excessive Oil Mist During a Fault Condition
If there is a fault condition and the opacity of the oil mist becomes greater than the setpoint for the alarm, the condition is indicated by the following display:
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| Illustration 10 | g00732573 |
Example of the display for excessive oil mist during a number 14 fault condition | |
- The red "Test" LED is switched ON.
- The red LED that is dedicated to the fault flashes.
- The red "Alarm" LED is OFF.
- The green "Ready" LED is OFF.
The "RESET" button can still be used to toggle the display for opacity.
"Alarm Level" Switch
The "Alarm Level" switch is used for increasing or decreasing the optical sensitivity. The switch is set at the factory to position number four. Although the position is not normally changed, the position of the switch can be adjusted in order to help avoid false alarms.
Consult Caterpillar, Inc. before you make any adjustments to the "Alarm Level" switch.
The switch positions and the sensitivity is listed in Table 2.
Note: The adjustment of the sensitivity is limited. If the opacity is adjusted to a maximum of 70 percent, the detector will generate a fault.
| Optical Sensitivity of the Oil Mist Detector | ||
| Switch Position |
% Opacity 191-6505 Oil Mist Detector |
% Opacity 149-5143 Oil Mist Detector |
| 1 | 0.5 | 0.7 |
| 2 | 1.0 | 1.1 |
| 3 | 1.5 | 1.6 |
| 4 | 2.0 | 2.4 |
| 5 | 3.0 | 3.7 |
| 6 | 5.0 | 5.5 |
| 7 | 7.0 | 8.2 |
| 8 | 10.0 | 12.4 |
| 9 | 15.0 | 18.5 |
| 10 | 25.0 | 27.8 |
Adjustment of the "Alarm Level" Switch
If the optical sensitivity of the oil mist detector is too high, false alarms can occur. If the optical sensitivity is too low, a fault will be generated. Consult Caterpillar, Inc. before you make any adjustments to the "Alarm Level" switch.
The following procedure for adjustment of the "Alarm Level" switch must only be performed by authorized personnel:
- Disconnect the electrical plug.
- Remove the electronic module. For instructions on removal and installation of the electronic module, see this Testing and Adjusting, "Repair" topic.
| NOTICE |
|---|
If the parts of the electronic module are touched, the module can be damaged. Handle the module only at the outside edges of the circuit board. |
- Use a screwdriver to adjust the "Alarm Level" switch.
- Install the electronic module.
- Install the measuring head.
- Connect the electrical plug.
After power is supplied to the detector, the detector will adjust for the change in optical sensitivity.
Relays
Ready Relay
The ready relay is switched ON during normal operation of the oil mist detector. The green "Ready" LED is illuminated when the ready relay is ON.
Alarm Relays
During normal operation, contacts 6 and 8 in the alarm relay are CLOSED.
The alarm relay is switched ON if the opacity of the oil mist exceeds the threshold. Contacts 6 and 8 are OPEN. Contacts 7 and 8 are CLOSED. The red "Alarm" LED is illuminated.
Another alarm relay is available for a customer connection. During normal operation, contacts 14 and 16 in this alarm relay are CLOSED.
The alarm relay is switched ON if the opacity of the oil mist exceeds the threshold. Contacts 14 and 16 are OPEN. Contacts 15 and 16 are CLOSED.
Schematic for the Terminals
Illustration 11 shows the schematic for the terminals for the oil mist detector.
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| Illustration 11 | g00733024 |