Gallery. 1  Hand-cranked planetary sharpener, with cover in place. 2  Hand-cranked planetary sharpener from 1950â60, with cover removed. 3  Hand-cranked planetary sharpener with spring-driven pencil holder. 4  AC-powered electric pencil sharpener. 5  Battery-operated sharpener.
Description. Tracking Error is a measure of how closely an ETF follows its benchmark index. This data point seeks to isolate the ability of the portfolio managers to track the index, ignoring the confounding effects of ETF liquidity on market prices.escription. Tracking Error is a measure of how closely an ETF follows its benchmark index. This data point seeks to isolate the ability of the portfolio managers to track the index, ignoring the confounding effects of ETF liquidity on market prices.
What does excess following error mean? When an axis can not physically keep up with the commanded control speed. Troubleshooting excess following errors. Causes for following error. Mechanical porblems that are causing a load on the axis. Either bearings, axis brake, lubrication, counterballance weight ect. Old or aging drives can also be the cause. Troubleshooting following errors