The accels rated max temp is 225F, and engine coolant temp is around 180F...I don't have thermocouple data for block surface temps but I have to imagine it's near the coolant temps.
The supply to the sensors is a current range of 2-20mA and my DAQ is setup to supply 8mA.
Sidenote, I've...
Yeah it is getting overloaded a bit, but we're starting to lean towards this being a ground loop that's causing interference on all the accels that are installed on the engine block. The overloads are all due to the pulses with are very short in duration...it's not creating a flat point in the...
Would a ground loop issue cause this? The block is grounded to the engine battery while the DAQ is grounded to earth through the wall outlet? I thought ground loops would give a 60hz noise spike but maybe it can throw a bunch of white noise in the signal too? I could see a gasket or something...
The engine is a V6...in the past I've exclusively worked with inline 6 engines which is why this stood out so much.
I was thinking it could be electronic interference, since it is a spark ignited engine (my past experience was diesel) but with 4 accels I should get varying degrees of noise...
Hello all,
I'm working on recording some vibration data for an engine block and the data has me a little confused. I've got 3 triaxial accelerometers installed at various locations on the engine block (front side, rear side, front face) as well as one installed on an EPR valve mounted on the...
It's listed as "Fatigue Life" but I have no idea where it comes from... I'm assuming it's some sort of calculated value since based of a line of best fit for the SN curve...because like you said they usually list it as a 10^6 type number. There are minimum and nominal fatigue lifes listed and...
Some info on the spring from the spec:
Beehive Compression Spring
Wire Diameter: 0.187"
OD: 1.194"
Installed Load: 105 lbf
Working Load: 280 lbf
Natural Freq: 532 Hz
Min Tensile: 296.5 ksi
% Tensile: 40.05% (Here's where I'm confused as to what this represents, is it torsional fatigue or...
Hello All,
I'm working on a project where we're having valve springs fail occasionally. I was tasked with measuring the stress levels on the coil of the spring and comparing them with the stated material limits from the supplier.
I have installed torsional strain gages (45 deg from center) on...
Hello All,
I've got accelerometer data from a running engine and the signal is confusing me. I'm looking at time domain vibration data and I'm seeing some very high impulse spikes that seem to line up with firing frequency. I normally would expect this however these spikes are all positive...
Hello all,
Got an easy one for you. I'm making up some lead wire extensions for a test and I need the name of a type of connector terminal. I have used in the past wire connection terminals where the connector is a spring loaded shaft with a slot in it that you can insert the open end of a...
