What is this symbol

[BeezFun]

I've got a problem with my boom lift which is 90% hydraulic and 10% electrical, and right now it's the 10% electrical that's not working. A symbol that looks like a capital "Z" appears next to some of the wire traces on the logic diagram for the machine, does anyone know what it means? The machine is made by Nifty Lift which is a British company, so maybe it's something more common on the other side of the pond. Normally Z means impedance, so I'm not sure if they're saying that's a high impedance path around the relay and, if so, what kind of device is providing the impedance.
Here's a small example, I've also included the full diagram so you can see all the places it appears, sometimes sideways.

 

[BeezFun]

I got an answer on Reddit. It's a symbol for a diode, which no one had ever seen before. But given the location is always around a relay, it must be there to prevent the the back emf when the coil is deenergized.

 

[caver]

I wonder if it's varistor (MOV) for the coil but odd drawing.

 

[Midniteoyl]

Diode Symbol is a Triangle with a line across the top..

 

[ning]

I haven't seen that symbol either... is it a zener diode?

 

[Midniteoyl]

I haven't seen that symbol either... is it a zener diode?

Zener Diode has a bent line:

 

[workinonit]

That looks like it would be a zener but it's not the symbol for one. Look at the circuit and see what the component looks like.

 

[BeezFun]

Once I knew I was looking for a diode I found them on the control board in between and around the relays, but they're hard to see without a good flash.

 

[2515R Dude]

In electronics, "Z" represents impedance, which is the overall opposition to the flow of alternating current (AC) in a circuit, encompassing both resistance and reactance.

Google Search

 

[WranglerX]

I think its a diode symbol by way its wired across relay coils....