Maximum Gage Excitation Voltage Limits for Task Balances

ARO-Inc.
Technical Memorandum
Number 57

Date: June 24, 1977
Subject: Maximum Gage Excitation Voltage Limits for Task Balances
From: D.D. McMurchy

General

A vital specification of a Task Balance is the maximum voltage that can be applied to the strain-gage bridge of a balance component. The maximum voltage is the excitation voltage limit that can be continuously applied to a gaged component without degrading the performance of the component. The performance of a balance will not be degraded if the combined temperature effects of the internal heating that is due to the gage power dissipation, and the the external heating that is due to the environment the balance is exposed to does not exceed 100 degrees F as sensed by the internal thermocouples of a balance. One or more of the thermocouples, depending on their availability in a particular balance, should be monitored when a balance is to be used in a testing application where the 100 degrees F limit may be a factor in determining the quality of the balance data.

Maximum Excitation Voltages for Task Balances

1. For Bridges of 350-ohm Resistance:

Balance Diameter Size	Maximum Gage Excitation Voltage
(Inches)	(Volts, dc)
0.75	8
1.00	10
1.50	12
2.00 –> 4.00	18

2. For Bridges of 120-ohm Resistance:
a. 0.75-inch diameter balance: 4.5 volts, maximum.
b. 1-inch diameter and larger balances: 6 volts, maximum.

NOTE: The temperature and voltage limits that are stated in this memo were obtained from Task Corporation.
ARO, Inc.
NAS2-6745