Situation
When customers make a payment towards either starting a Dryer, or adding additional time to a Dryer that's already running, the machine is adding more, or fewer, minutes than what is desired/configured via the Card Reader's settings on the LaundroPortal.
It is important to note that not all Card Reader's will have Dryer dry time settings. In general, only Pulse Communication Card Reader's will display Dry TIME settings. At this time there is on 1 specific Serial Communication Card Reader Control Type that displays any Dry TIME settings.
Explanation
The Vast Majority of Card Reader's installed on Dryers DO NOT have the ability to control the amount of time the Dryer adds, whenever it receives payment.
Many Card Readers installed on Dryers are simply emulate a Coin Drop (Pulse Communication Card Readers).
On these readers, once you present the card to it, the reader takes the money (according to the "Time Unit Cost" setting that's been entered in the reader's settings) and sends 1 pulse to the machine to tell it to start.
The reader is NOT communicating with the machine directly, so it has no way of programming, configuring, or controlling the machine with the amount of Dry time it should be adding per pulse.
The "Time Unit (mins)" setting in the reader, as shown above, is ONLY for Card Reader simulation purposes (so the reader can display "busy" for the correct amount of time, and send out any notification texts about the machine's cycle being complete).
The actual drying time added per pulse is completely set, and controlled by the machine entirely.
You will want to have the "Time Unit (mins)" setting on the reader synchronized with the actual dry time setting inside the machine control; but the actual dry time the machine will add is always controlled by the machine directly.
The special case of Serial communication Card Readers, that does have the ability to affect the machine's Dry Time, is an Alliance Machine with an ACA Control board installed.
On these machines, the Card Reader has the ability to update the amount of Top Off time the Dryer adds (amount of time added once the Dryer is already running a cycle.
These Card Readers CANNOT control the amount of time the Dryer adds when starting a cycle.
On Serial Control machines, you also need to program the amount of dry time, on the Dryer directly. With Serial communication Card Readers, you will NOT see a Dry time setting (with the 1 exception mentioned about), because the Card Reader is in direct communication with the machine, so the Card Reader will know the dry times by communicating with the machine directly; so still need to program the dry time on the physical machine to get them to add the correct/desired amounts of time per payment.
So in summary, if a Dryer is not adding the correct amount of time per payment, you need to adjust the dry time setting on the machine directly.
If you're machine uses Pulse Communication Card Readers, you'll also need to adjust the Card Reader's "Time Unit (mins)" setting to match whichever you've set the machine's dry time to.