The response time of the MOV is largely ambiguous

The response time of the MOV is largely ambiguous, as no AD1885 standard has been officially defined. The sub-nanosecond MOV response claim is based on the material's intrinsic response time, but will be slowed down by other factors such as the inductance of GT30J322 component leads and the mounting method. That response time is also qualified as insignificant when compared to a transient having an 8 |¨¬s rise-time, thereby allowing ample time for the BTS781GP device to slowly turn-on. When subjected to a very fast, <1 ns rise-time transient, response times for the MOV are in the 40-60 ns range.Typical capacitance for consumer-sized (7 20 mm diameter) varistors STRM6524 are in the range of 100-1,000 pF. Smaller, lower-capacitance varistors are available with capacitance of ~1 pF for microelectronic protection, such as in cellular phones. These 1115A low-capacitance varistors are, however, unable to withstand large surge currents simply due to their compact PCB-mount size.