Does Strain Gage Resistance Matter?

With foil strain gages available with starting resistances from 60 Ω to 5000 Ω, does it really matter which value you choose? Well, like many choices in life, your resistance selection will involve trade-offs. Let's say you choose a higher strain gage resistance. On the plus side, it will provide lower current for equal bridge voltage, which results in less grid self-heating and potentially better resistance stability over time. In addition, there will be higher bridge output when bridge excitation is increased and the lead-wire resistance will have less influence. On the negative side, the gages are usually more expensive and have less commercial availability, and they may not match bridge completion resistors in some instrument systems.