luci-app-nut input validation error

I'm luci-app-nut.

When altering the the field [Off Delay(s)] under the driver config it requires an integer. When inputting for example 120 it gives the error:

/usr/lib/lua/luci/model/cbi/nut_server.lua:186: attempt to compare nil with string
stack traceback:
	/usr/lib/lua/luci/model/cbi/nut_server.lua:186: in function 'validate'
	/usr/lib/lua/luci/cbi.lua:1426: in function 'parse'
	/usr/lib/lua/luci/cbi.lua:1562: in function 'parse'
	/usr/lib/lua/luci/cbi.lua:248: in function 'parse'
	/usr/lib/lua/luci/cbi.lua:1184: in function 'parse'
	/usr/lib/lua/luci/cbi.lua:248: in function 'parse'
	/usr/lib/lua/luci/cbi.lua:387: in function 'parse'
	/usr/lib/lua/luci/dispatcher.lua:1410: in function '_cbi'
	/usr/lib/lua/luci/dispatcher.lua:1056: in function 'dispatch'
	/usr/lib/lua/luci/dispatcher.lua:483: in function </usr/lib/lua/luci/dispatcher.lua:482>

Start at /usr/lib/lua/luci/model/cbi/nut_server.lua around line 186 and reproduce the error by changing the driver config's Off Delay(s) field to 120. Inspect the validate function and confirm the field accepts an integer without raising the reported comparison error; verify the form can be submitted successfully.