CM -

CM

Type CM is a classic on-load tap changer composed by diverter switch & tap selector. It covers the widest application range from small power up to large power transformers. After a long history of operation and modifications, today type CM is one of the most reliable tap changers, which is able to withstand heavy duty with over 1,000 daily operations in furnace application.

Item	Specification		CMⅢ 500Y CMⅠ500	CMⅢ 600Y CMⅠ600	CMⅠ800		CMⅠ1200	CMⅠ1500
1	Max. rated through-current (A)		500	600	800		1200	1500
2	Rated frequency (Hz)		50 or 60
3	Connection		Three-phases for neutral point of star connection Single-phase for any selectable winding connection
4	Max. rated step voltage (V)		3300
5	Rated step capacity (kVA)		1400	1500	2000		3100	3500
6	Short-circuit current test (kA)	Thermal (3s)	8	8	16		24	24
		Dynamic (Peak)	20	20	40		60	60
7	Max. Operating Positions	Without change-over selector	18 (special linear regulation can be up to 34)
		With change-over selector	35 (special multiple coarse regulation can be up to 107)
8	Insulation to ground (kV)	Highest voltage for equipment Um	72.5	126	170	252		300
		Rated separate source AC withstand voltage (kV/50Hz,1min)	140	230	325	460		480
		Rated lightning impulse withstand voltage (kV,1.2/50μs)	350	550	750	1050		1100
9	Tap selector		4 grades of B, C, D and DE according to insulation level
10	Mechanical life		Not less than 800,000 operations
11	Contact life		Not less than 200,000 operations
12	Oil compartm-ent of diverter switch	Service pressure	0.03Mpa
		Leakage test	No leakage under 0.08Mpa for 24 hours
		Over pressure protection	Bursting cap busts at 300 ± 20%kPa
		Protection relay	Oil flow speed set at 1.0m/s ±10%
13	Motor drive unit		SHM-D or CMA7
14	Oil filter plant		ZXJY-1 /ZXJY-2 /ZXJY-3 according to requirement