Asp.Net Client Certificate Authentication - Issue with website re-prompting for client PIN

Question

I have an ASP.NET 5 web application that is setup to use client certificate authentication, specifically a DoD CAC. I followed Microsoft's guidance (here) to setup the server and application to prompt for the client certificate. The implementation works except the website will prompt the user to re-enter their PIN at the 60 minute mark, which is not acceptable by the end user.

This particular application is intended for long use; approximately 8-12 hours at a time. The main application view displays a data table and uses JavaScript to fetch the data approximately every 60 seconds from an embedded web api controller (e.g. /api/xyz/123)

I'd like to adjust the rate at which the user is re-prompted for their PIN, but I cannot find any information on the topic. Like, what system is responsible for initiating the PIN prompt; a policy on the client certificate; a setting on the host server; or an application config setting?

I've had no luck tinkering with settings on the application or host server and cannot find any documentation on the topic. I would greatly appreciate any guidance.