Pulse or dimmer setting on herpstat?

Sorry if this is in the wrong place, but I finally ordered a herpstat for my rack. ($150 ouch) The herpstat says it has two proportional modes, dimmer and pulse. What should I use? Thanks!

Dimmer for racks IMO. Instead of pulsing 100% of power on and off at fast intervals, it trickles the current down to a percentage and holds it more constant in my mind, and reduces energy cost in my thoughts. . . example - my racks run around 30% power for a 3 high CB-70 rack with 4" flexwatt on a Herpstat 1. My Radiant Heat Pannels are on dimming as well, and it seems to work quite well, though I may play around with it later on.

The pulse option is intended for metal racks since dimming can sometimes cause a humming noise.

Yup what Brian said.

from spyder robotics


The Intro does have " Advanced diming proportional control" checked. That’s
the standard of all of our products. We recently added pulse proportional
to the Herpstat 1/2 models but the intro doesn't really need it as the only
real advantage of pulse proportional is avoiding hum with metal racks which
the intro (being a non-grounded anyway) is not marketed for.

Directly from the user manual:

Output Mode: (Heat (Dimming), Heat (Pulse), Cooling)

Note: When the Mode is changed all settings for the selected output will be set to the defaults.

Heat (Dimming) can adjust the voltage output to the heating device similar to a household dimmer. In most
cases this is the best performing mode of control.

Heat (Pulse) can provide varied lengths of pulsed power to the heating device. This method of control can help
avoid the audible hum on metal rack systems .