TB 9-4920-454-24
IDENTIFICATION AND DESCRIPTION
1. Test Instrument Identification.
This bulletin provides instructions for the
calibration of Tester, Exhaust Gas Temperature, Howell Instruments, Inc., Model
BH112JB-( ). The manufacturer's manual and TM 55-4920-401-13&P were used as the
prime data sources in compiling these instructions. The equipment being calibrated will be
referred to as the TI (test instrument) throughout this bulletin.
a. Model Variations. None.
b. Time and Technique. The time required for this calibration is approximately
6 hours, using the dc and low frequency technique.
2. Forms, Records, and Reports
a. Forms, records, and reports required for calibration personnel at all levels are
prescribed by TB 750-25.
b. Adjustments to be reported are designated (R) at the end of the sentence in which
they appear. When adjustments are in tables the (R) follows the designated adjustment.
Report only those adjustments made and designated with (R).
3. Calibration Description. TI parameters and performance specifications which
pertain to this calibration are listed in table 1.
Table 1. Calibration Description
Test instrument parameters
Performance specifications
Range: 0 to 1399 oC
Temperature
2 oC
Accuracy:
% RPM
Range: 0 to 119.90% rpm
Accuracy: ±0.1% rpm
Standard day measurements, ambient Range: -41 to 139 oF
Accuracy: ±4 oC
temperature, and % RPM
±0.5% rpm
Range: 4.21 , 8.0
A
15.0 , and 22.0
S ccuracy: ±0.05
EQUIPMENT REQUIREMENTS
calibration procedure. This equipment is issued with Secondary Transfer Calibration
Standards Set AN/GSM-286; AN/GMS-287 or AN/GSM-705. Alternate items may be used by
the calibrating activity. The items selected must be verified to perform satisfactorily prior
to use and must bear evidence of current calibration. The equipment must meet or exceed
four-to-one ratio between the standard and TI. Where the four-to-one ratio cannot be met,
the actual accuracy of the equipment selected is shown in parenthesis.
