Dynamic TCH timer

In ZTE Equipment when a dynamic TCH is converted to on demand PDCH and then it become IDLE state then how long BSS will wait to convert it back to CS resources in ZTE?
In Ericsson there is one Time PILTIMER but i want to know same parameter in zte.
When an on-demand PDCH becomes idle it is placed in idle list for the packet switched domain and parameter PILTIMER is started. When the parameter PILTIMER expires for a PDCH the channel is returned to circuit switched domain. When an on-demand PDCH becomes idle it is placed in idle list for the packet switched domain and parameter PILTIMER is started. When the parameter PILTIMER expires for a PDCH the channel is returned to circuit switched domain.

Thanks in advance.