PWM (Pule Width Modulation) charge controllers are output amperage limited and input voltage tolerant.  They use a different method of managing the difference between the input voltage and current and the output voltage and current vs. MPPT controllers.  Like MPPT controllers, higher the voltage of the array and higher the battery bank voltage will allow more controller capacity.  These types of chargers are about 30% less efficient that a comparable MPPT, but more cost sensitive and the situation may not warrant high efficiency.

Morningstar TriStar PWM 45 and TriStar PWM 60 have an output current capability of 45 and 60 Amps respectively.  The Renogy Rover 60 has an output of 60 Amps.  The input open-circuit voltage tolerance for all of these models is 150VDC.  Three different scenarios might look like this:

Maximum Input Voltage = 150VDC.  This means that with a typical 350W class panel with a Voc of 48V that up to 3 panels could be connected in series for a Voc of 144VDC.

Maximum Theoretical input Power = 3 panels x 350W/panel = 1050W.

Maximum Output Power = 12V x 45A = 540W.

In this case the output power will be limited by the battery voltage.  The solar panels are overbuilt, which is not a bad this in this situation because they will produce the maximum 720W output even in lower light conditions such as dusk and dawn or shorter winter days.  The solar panels could also be lessened to a 2S1P configuration with a total panel power of 700W.

Maximum Input Voltage = 150VDC.  This means that with a typical 350W class panel with a Voc of 48V that up to 3 panels could be connected in series for a Voc of 144VDC.

Maximum Theoretical input Power = 3 panels x 350W/panel = 1050W.

Maximum Output Power = 24V x 45A = 1080W.

In this case the output power and input power are almost an exact match.

Maximum Input Voltage = 150VDC.  This means that with a typical 350W class panel with a Voc of 48V that up to 3 panels could be connected in series for a Voc of 144VDC.

Maximum Theoretical input Power = 3 panels x 350W/panel = 1050W.

Maximum Output Power = 48V x 60A = 2880W.

In this case the output power will be limited by the solar array.  The solar panels are underbuilt because they are in a 3S1P (3Series, 1Parallel) configuration.  To get maximum power a 3S3P configuration should be used.  The input voltage remains at 144VDC, but the Maximum Theoretical input Power is now: 9 panels x 350W/panel = 3150W.

The handy table below shows the maximum capability of the Morningstar TriStar and Renogy Rover charge controllers based on output current and battery voltage.