| Meas No. | TTS TITLE | MEASUREMENT | DESCRIPTION | Expected DN V1, V2 |
MEASUREMENT RANGE | MEASUREMENT RESOLUTION |
|---|---|---|---|---|---|---|
| E-452 | LEPT T | LECP LEPT TEL TEMP\n(Transducer Disconnected) | This measurement is sampled by two temperature transducers mounted in the D2 detector holder near the 2µ detector. It measures the temperature of the critical thin detectors (2 µ and 5 µ) in the LEPT and gives a general knowledge of the overall LEPT telescope temperature. The LECP detectors must not exceed +35°C. | – | -78°C to +100°C | 0.7°C / DN |
| E-453 | LECP TE T | LECP LEMPA TEL TEMP | This measurement is sampled by a transducer mounted on the LEMPA telescope and measures the overall temperature of the telescope. The measurement is used to monitor the controlled temperature of the telescope. | 90, 95 | -78°C to +100°C | 0.7°C / DN |
| E-454 | LP LEPT-6 | -6 V LEPT | This measurement measures the voltage (nominal -6 V) to the LEPT discriminators, identification circuits, and coincidence logic. The nominal analog level is 1.2 V. Measurement of a power monitor and loss makes interpretation of LEPT health difficult if measurement lost. | 84, 84 | 0 to -15 V | 0.0586 V/DN |
| E-455 | LP PWR-6 | -6 V | This measurement measures the voltage (nominal -6 V) from the instrument power supply. The nominal analog level is 1.2 V. Loss of measurement makes determination of instrument health difficult. Loss of -6 V means loss of instrument. | 105, 105 | 0 to -15 V | 0.0586 V/DN |
| E-458 | LP DS-12 | -12V DATA SYSTEM | This measurement measures the voltage (nominal -12 V) to the data system. The nominal analog level is 2.4 V. PHA identification and priority bits would be bad and data system timing would be affected if lost. | 212, 210 | 0 to -15 V | 0.0586 V/DN |
| E-459 | LP MTR T | MOTOR TEMPERATURE | This measurement provides the stepping motor temperature. The temperature transducer is mounted on one of the legs of the motor support. The nominal analog output range is 0-1.6 V. | 195, 195 | – | – |
| E-460 | LP SBPWR- | -STEPPER BASE POWER | This measurement measures the voltages (nominally -6 V and -12 V) to EB-1 (LEPT amplifiers). The nominal analog level is 1.6V. Loss of measurement reduces the ability to verify LEPT performance. Loss of function implies loss of LEPT. | 133, 132 | – | – |
| E-461 | LP LOGAMP | LOG AMP TEMPERATURE | This measurement provides temperatures of the critical log amplifiere. The temperature transducer is mounted on the mother board near the log amplifiers. The nominal analog output range is 0-1.6 V. Loss of measurement means loss of capability to apply needed correction factor to data. | 113, 116 | – | – |
| E-462 | LP DS+8 | + 8 VDATA SYSTEM | This measurement measures the voltage (nominal +8 V) to the data system, motor control, ⍺, β, 𝛄 discriminators, and platform command decoder. The nominal analog level is 1.6 V. Loss of measurement reduces diagnostic capability. Loss of function means complete loss of instrument. | 138, 134 | 0 to +15 V | 0.0586 V/DN |
| E-464 | LP SBPWR + | +STEPPER BASE POWER | These measurements are the voltages (nominally +6 V and +12 V) to EB-1 (LEPT amplifiers). The nominal analog level is 1.5 V. Loss of measurement reduces the ability to verify LEPT performance. Loss of function means loss of LEPT. Expected DN 128 on V1, 123 on V2 | 128, 123 | – | – |
| E-465 | LP DS+6 | +6 V DATA SYSTEM | This measurement measures the voltage (nominal +6 V) to the data system. The nominal analog level is 1.2 V. Loss of measurement reduces the ability to assess validity of analog commutator results. Loss of function means lose the ability to read analog commutator voltages. | 103, 101 | 0 to +15 V | 0.0586 V/DN |
| E-466 | LP BILOW | BIAS MONITOR 1 | This measurement measures the input voltages to the bias network. The nominal analog level is 1.5 V. Loss of measurement makes is difficult to determine if detectors are correctly biased and if normal or reduced bias is being used. Loss of detector biases would be catastrophic. | 124, 86 | – | – |
| E-467 | LP LEP+12 | +12 V LEPT | This measurement measures the summation of the voltages (nominally +6 V and +12) to LEPT high. A summation is used because both voltages can then be read using only one channel. The nominal analog level is 1.5 V. Loss of measurement makes it difficult to determine the correct performance of LEPT high. Loss of function means LEPT high only is lost. | 125, 123 | – | – |
| E-468 | LP BIHIGH | BIAS MONITOR 2 | This measurement measures the detector high voltage bias values. Nominal analog level ie 0.32 V. Loss of measurement makes it difficult to determine if all but the thin detectors are operating. Loss of function means loss of detectors. | 31, 20 | – | – |
| E-469 | LP DS+12 | +12 V DATA SYSTEM | This measurement measures the voltage (nominal +12 V) to the interface circuits and ⍺, β discriminators. The nominal analog level is 2.4 V. Loss of measurement impairs determination of instrument performance. Loss of function means loss of communication with instrument. | 199, 193 | 0 to +15 V | 0.0586 V/DN |
| E-470 | LP PWR+5 | +5 V | This measurement measures the voltage (nominal +5 V) from the instrument power supply. The nominal analog level is 1.0 V. Loss of measurement makes it difficult to determine instrument functioning. Loss of -6 V means loss of instrument. | 89, 85 | 0 to +15 V | 0.0586 V/DN |
| E-471 | LP PWR+6 | +6 V | This measurement measures the voltage (nominal +6 V) power supply. The nominal analog level is 1.2 V. Loss of measurement makes interpretation of LEPT health difficult. Loss of function means LEPT is lost. | 102, 101 | 0 to +15 V | 0.0586 V/DN |
| E-472 | LP PWR+30 | +30 V | This measurement nominally indicates one half of the input to the LECP stepper motor which is powered from the 30V dc supply. It senses the voltage between 30 V supply and chassis ground which is nominally 15 V; the remaining 15V is between chassis ground and 30 V Rtn. This measurement, the only one on the S/C to do so, provides intelligence on 30 V bus imbalance; i.e., voltage between chassis ground and 30 V supply and between chassis ground and 30 V return.\n | 110, 53 | 0 to +60 V | 0.234 V/DN |
| E-473 | LP PWR+8 | +8 V | This measurement measures the voltage (nominal +8 V) from the instrument power supply. The nominal analog level is 1.6 V. Measurement is a power monitor and loss makes interpretation of LEPT health difficult. Loss of function means LEPT is lost. | 138, 135 | 0 to +15 V | 0.0586 V/DN |
| E-474 | LP LEPT+6 | +6 V | This measurement measures the summation of the voltages (nominally +6 V and +12 V) to LEPT low. A summation is used because both voltages can then be read using only one channel. The nominal analog level is 1.2 V. Loss of measurement makes it difficult to determine correct performance of LEPT low. Loss of function means LEPT low only is lost. | 126, 123 | – | – |
| E-475 | LP PWR+12 | +12 V | This measurement measures the voltage (nominal +12 V) from the instrument power supply. The nominal analog level is 2.4 V. Measurement of a power monitor and loss makes interpretation of LEPT health difficult. Loss of function means LEPT is lost. | 199, 194 | 0 to +15 V | 0.0586 V/DN |
| S-457 | LECP IA | LECP I-ALPHA CURRENT | This measurement is a 10 bit binary word which measures the leakage current in the ⍺ detector. Loss of measurement means loss of knowledge of leakage currents in the ⍺ detector. Loss of function means minor loss of science data at near encounter. Near encounter mode only?? | – | 5 nA - 5 uA | 5 nA/bit |
| S-458 | LECP IB | LECP I-BETA CURRENT | This measurement is a 10 bit binary word which measures the leakage current in the β detector. Loss of measurement means loss of knowledge of leakage currents in the β detector. Loss of function means minor loss of science data at near encounter. Near encounter mode only?? | – | 5 nA - 5 uA | 5 nA/bit |
| S-459 | LECP MODE | LECP MODE | This meaeurement is the FDS / LECP mode indicator. It appears as bit 112 of GS-3 minor frame 72, the LSB of the 16 bit status word. "0" indicates far encounter and "1" indicates near encounter. Loss of measurement is not significant because the LECP mode could still be inferred by observing that the data will be scrambled after the LECP goes to near encounter and then clear up after the FDS bit goes high ("1"). If the FDS lost the capability to raise thie bit to high, the LECP would lose the near encounter capability and only be capable of far encounter functions.\n | – | – | – |
| S-461 | LECP CMD2 | LECP COMMAND WORD 2 | This measurement consists of a 12 bit word. The bits are defined in Table 25-3. Bits one and two are not used. Loss of measurement means loss of direct visibility of the LECP command 2. The loss of this measurement does not effect the ability to command the instrument. | – | – | – |
| S-462 | LECP CMD3 | LECP COMMAND WORD 3 | This measurement consists of a 12 bit word. The bits are defined in Table 25-4. Bits one and two are not used. Loss of measurement means loss of direct visibility of the LECP command word. The loss of this measurement does not effect the ability to command the instrument. | – | – | – |
