XC43 PWM out HS+LS internal free wheeling diode

Shannon Tyler 8 months ago in IQANdesign updated 8 months ago 2

We are swapping out from the XA2 to the XC43 and we originally thought we were going to be using the PWM HS output so we attached a ark suppressing diode on the 4-way 3-pos cart valve (HSP 10-47CB-0-v-24ER). We however ended up using the PWM HS-LS output which has a internal free wheeling diode. Is the newly installed ark suppression diode going to case problems down the road. and is it best practice to just use the internal diode on the PWM HS+LS output?


I checked the coil, that looks like a device where you would not need to use open control PWM, but could use closed loop current controlled PWM. In IQANdesign you could then configure it as COUT instead. 
See discussion why PWM instead of COUT? / Hardware / IQAN

For COUT, it is better to use the internal circulation didode. (See MC4x instruction book) 

An external diode influence the current measurement and give worse results. You won't be damaging anything though. 

PWM-B: C1:15 (HS), C1:40 (LS+), C1:56(LS-)


COUT-B: C1:15 (HS), C1:40 (LS+), C1:56 (LS-)

DOUT-K: C1:45 (HS), C1:40 (LS)

DOUT-L: C1:45 (HS), C1:56 (LS)

I guess they originally tried to use the COUT out in previous models. They said they were getting a lot of nuisance system generated codes. so, a switch to the PWM was made to get rid of the diagnostics.  above is how they have the signal going out.