Grounding 1 leg of Control Transformer

[bpk]

Is there anything wrong about grounding a leg of a 24v control transformer ? The specific installation I have is an electronic switch / latching realy that requires 0 and 24 volts. I think I have seen them grounded before in control panels but Im unsure if its common practice or only a specific installation or transformer when it can be done.

 

[Smart $]

Is there anything wrong about grounding a leg of a 24v control transformer ? The specific installation I have is an electronic switch / latching realy that requires 0 and 24 volts. I think I have seen them grounded before in control panels but Im unsure if its common practice or only a specific installation or transformer when it can be done.

Nothing wrong with grounding one side. In fact it is required under certain conditions [250.20(A)].

 

[jusme123]

read 250.30(A)(1)exception(3) ['08 NEC]

 

[jusme123]

250.30(A)(1)exception(3)
Exception No. 3: The size of the system bonding jumper
for a system that supplies a Class 1, Class 2, or Class 3
circuit, and is derived from a transformer rated not more
than 1000 volt-amperes, shall not be smaller than the derived
ungrounded conductors and shall not be smaller than
14 AWG copper or 12 AWG aluminum.