Tcrgolf, my Chevy one ton DRW crew cab diesel has a GVW of 13,200 and weighs about 8300. My combined GVW is about 22,000 lbs so with my 5th wheel at 9,200 and my truck weight, I am about 5,000 lbs under the sticker limit.
I might add to what Suzi had to say about closures, one trip, we were stuck for about three days on the Cassiar Hwy due to washouts. We had them on both sides of us, ahead and behind. Must have been about 10 or 12 vehicles stuck there together. Luckily most were RVs so there was plenty of food and drink for everyone. Had a couple of OTR truckers and a couple of tent campers. So it was one big pot luck three times a day. Fired up my 4 KW generator every morning and put a couple of pots of coffee on to cook outside my rig. Anyone that wanted a cup could stop by to serve themselves. Then we would have a group breakfast of donated food. It was actually a lot of fun, as I think back to that trip. Both truckers had sleepers on their cabs so everyone was set to stay and had a place to sleep. That was probably the most time I ever ran my generator as I dislike the sound of them greatly.
Thanks to Suzi I now know what a PD machine is, now to look up what it does. In the 15 years I rode in the back of ambulances as a cardiac medic, don't remember every running into such a machine. Lots of renal dialysis machines in hospitals. Learn something new every day on this forum.
On edit: Just did a google search on the PD machines. I continue to be amazed at the progress of medical treatment these days. So the 600 watts would be just over 5 amps at 120 volts. My Honda 2000I will pull 16 amps intermittently and 13.3 amps continuously they claim, and is somewhat quite. To use a bit of interpolation then a Honda 1000i should pull 8 amps intermittently and 6+ all the time. Plenty for a 600 Watt load. I borrowed a 1000i one time from a friend to be able to watch TV after one of the hurricanes that hit us here in south Florida. Had it running on my front porch and it was very quite, easy to start, easy of fuel and ran like it was supposed to do.
Any of the good inverter generators should work just fine, as you might not have to use it very often but would have it if needed. Check around on sales for inverter generators, Camping World sells a brand, lots of us like Honda and Yamaha brands and there are others.