Experimental Investigations of the Seismic Performance of a Base-Isolated Uninterruptible Power Supply (UPS) through Shaking Table Tests

Table 7

Dynamic parameters of the UPS.

Parameters	Values
	SDOF1			SDOF2
	X-dir.	Y-dir.	Z-dir.	X-dir.	Y-dir.	Z-dir.
Damping ratio (%)	9.1	6.3	1	8.7	7.3	1
Effective stiffness (kN/m)	1,494	5,279	65,376	107,174	10,329	496,004
Transformer mass, m1 (kg)	460			—
Cooling system mass, m2 (kg)	—			300