Synchro/Resolver Measurement (Module S*)68C3 Operations Manual North Atlantic Industries, Inc. 12/19/2014Rev: 2014-12-19-0947 www.naii.com Page 227 of 330A & B ResolutionType: binary wordRange: N/ARead/Write: R/WInitialized Value: N/AIndividually configure encoder output resolution or commutation for each channel.REGISTER D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 FUNCTIONA & B RESOLUTION D X X X X X X X X X X X X D D D D=DATABITInteger 0 0 0 0 0 16 bit Encoder ResolutionInteger 1 0 0 0 1 15 bit Encoder ResolutionInteger 2 0 0 1 0 14 bit Encoder ResolutionInteger 3 0 0 1 1 13 bit Encoder ResolutionInteger 4 0 1 0 0 12 bit Encoder ResolutionInteger 32768 1 0 0 0 4 Pole CommutationInteger 32769 1 0 0 1 6 Pole CommutationInteger 32770 1 0 1 0 8 Pole CommutationSignal Loss ThresholdEach individual channel input signal voltage “VL-L” is measured and the value reported to a corresponding readregister. The signal loss detection circuitry can be tailored to report a signal loss (at SIG Status register) at a userdefined threshold. This threshold can be set to a resolution of 10 mv rms. Program the threshold by writing the value ofthe voltage threshold in integer decimal format. For example, if channel 1 input signal loss voltage threshold is to be 7VRMS, the programmed word to the corresponding register would be 700 (2BCh).Reference Loss ThresholdEach individual channel input reference voltage “VREF” is measured and the value reported to a corresponding readregister. The reference loss detection circuitry can be tailored to report a reference loss (at REF Status register) at auser defined threshold. This threshold can be set to a resolution of 10 mv rms. Program the threshold by writing thevalue of the voltage threshold in integer decimal format. For example, if channel 1 input reference loss voltagethreshold is to be 20 VRMS, the programmed word to the corresponding register would be 2000 (7D0h).Velocity ScaleType: 16-bit unsigned integerRange: 11.9209 rps to 190.7348 rpsRead/Write: R/WInitialized Value: N/AThe velocity scale factor is used to achieve a greater resolution at lower rotational speeds (rps). The scale factor is:4096 (190.7348 rps / max rps), where the max rps is selected by the user to achieve the maximum resolution for adesired RPS. Enter the scale factor as an integer to the corresponding Velocity Scale register for that particularchannel.(7FFFh) being 190.7348 rps for CW rotation, and -32,768 (8000h) being 190.7348 rps for CCW rotation). Scaling affectsonly the Velocity output word and not the dynamic performance.Examples: To get a maximum velocity word (32,767) @ 190.7348 rps, Scale Factor = 4096 (190.7348 / 190.7348) = 4096 =1000h; this is a velocity resolution of: (190.7348 rps/32,767) x 360/rps = 2.0955 /sec (factory default) To get a maximum velocity word (32,767) @ 63.5783 rps, Scale Factor = 4096(190.7348/63.5783) = 12,288 = 3000h;this is a velocity resolution of: (63.5783 rps / 32,767) x 360/rps = 0.6985 /sec To get a maximum velocity word (32,767) @ 11.9209 rps, Scale Factor = 4096(190.7348/11.9209) = 65,520 = FFF0h;this is a velocity resolution of: (11.9209 rps / 32,767) x 360/rps = 0.1310 /sec (lowest setting)REGISTER D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 FUNCTIONVELOCITY SCALE D D D D D D D D D D D D D D D D D=DATA BIT
