To determine the amount of Amperage Points/CTs needed in your assembly for ever meter point, it will vary on the voltage system.

120V_1ø2 wire voltage systems require 1 CT per meter point (1:1).
120/240V_1ø3 wire and 120/208V_2ø3 wire voltage systems require 2 CTs per meter point (1:2).
120/208V_3ø4 wire, 240/416V_3ø4 wire, 277/480V_3ø4 wire, 347/600V_3ø4 wire, 208V_3ø3 wire, 416V_3ø3 wire, 480V_3ø3wire and 600V_3ø3 wire voltage systems require 3 CTs per meter point (1:3).

Solid Core

The window size varies on the amperage
Ratio	Inside Diameter Inches	Outside Diameter Inches	Thickness Inches	Weight gr/lbs	Lead Length in ft.	MC Approval	UL FIle
100:0.08	0.5	1.1 x 1.2	0.78	69 / 0.15	6	AE-2486	UL2808, File No. E515601
200:0.1	0.76	1.8	0.7	100 / 0.22	6	AE-248	UL2808, File No. E515601
200:0.08	0.76	1.8	0.7	100 / 0.2	6	AE-2585	UL2808, File No. E515601
400:0.1	1.69	3.07	1	254 / 0.5	6	AE-2566	UL2808, File No. E515601
400:0.08	1.69	3.07	1	254 / 0.56	6	AE-2566	UL2808, File No. E515601
600:0.1	3.54	5.7	1	655 / 1.44	6	AE2566	UL2808, File No. E515601
600:0.08	3.54	5.7	1	655 / 1.44	6	N/A	UL2808, File No. E515601
800:0.1	5.9	8.66	1.57	1,587 / 3.5	6	AE-2566	UL2808, File No. E515601
800:0.08	5.9	8.66	1.57	1,587 / 3.5	6	N/A	UL2808, File No. E515601
1000:0.1	5.9	8.66	1.57	1,587 / 3.5	6	N/A	UL2808, File No. E515601
1000:0.08	5.9	8.66	1.57	1,587 / 3.5	6	N/A	UL2808, File No. E515601
200:5	3/4	2	0.6		2	AE-1368 rev.1	C/US UL recognized
400:5	1 1/2	3 1/2	0.9		2	AE-1180	CSA & UL recognized
600:5	3 1/4	2.78	5.6 X 5.6		NO Leads	T-188	CSA & UL recognized

Split Core

The window size varies on the amperage:
Window	Lead Length
100:0.033A - 0.75"	2ft. Note: To be used with a Multiplier of 3 or special programming of the i-meter45
100:0.1A - 0.75"	2ft.
200:0.1A - 0.75"	2ft. Note: Recommended for use with the MF-Series Meter and i-meter-636
400:0.1A - 1.25"	2ft.