> Date: Tue, 15 Dec 2015 12:55:51 -0500 > From: Neil > Subject: [EE] Interesting injector behaviour > To: "Microcontroller discussion list - Public." > Message-ID: <56705427.5020005@narwani.org> > Content-Type: text/plain; charset=3Dutf-8; format=3Dflowed >=20 > On a side note, I tried using a peak-and-hold injector as a regular=20 > high-impedance injector, with a 5.5-ohm series resistor to limit the max= =20 > current, similar to what some automotive ECU's do. This behaviour was=20 > interesting. Note that the max current is developed in 2 ms, but then=20 > the injector does not begin to open until at least another couple ms=20 > later. I just find this odd. The current here is measured across a=20 > 0.05-ohm sense resistor between the MOSFET source and ground. > http://tinyurl.com/za44qlz >=20 I would take a guess that that injector was not designed to be used with a = series resistor, I suspect that the resistor is limiting the power in the i= njector too much during the peak phase and you may well find that at elevat= ed temperatures the injector will not open. I recently tested another low-z injector in a stock set up that consists of= a high-load side driver with a 270mR current sense resistor feeding into a= comparator based circuit. The injector is 1.6mH, approx. 1.2R and opens in= 640us. It behaves in the same manner as other low-z injectors that I have = worked with. =20 http://www.rhinoman.org/rusefi/inj_4_51ms.jpg =20 regards James =20 =20 =20 --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .