I need design one circuit to activate one relay that the coil works at 110Vcd.
I have one previous design with one reed relay that yours contacts activate the coil of the relay at 110Vdc.
In some cases, the reed relay is broken (the contact NormalOpen is internaly cortocircuited). Why protection I can put in this reed relay?
I'm not sure if I understand you.
You want to drive a coil with 110 VDC? And use a reed relay to control 110 VDC?
I would think your relay is dead due to "inductive kickback".
When you energize the coil with DC it makes a field.
Then when you open the relay the field collapses. That collapsing field makes
a huge voltage/current. You need a diode to provide that voltage a path to ground.
You will have the same problem with MOSFET.
Use the reed relay with a diode. note: line towards more positive side of coil.