question

jamierob avatar image
jamierob asked

Cerbo GX versus Ekrano GX - relay not for 48v systems?

I have a 48v system and am planning to use some 48v pad heaters in my battery box to keep them above freezing. I plan to control them with the cerbo GX temp sensor and the cerbo gx relay. I plan to have 4x pad heaters for a total of 0.5A @ 48v for a total of 2.0A @ 48v. Since this is greater than the relay is rated for (DC up to 30VDC: 6A - DC up to 70VDC: 1A), I plan to use the solidswitch104 in order to not overload the relay.

I was planning on then upgrading to the Ekrano GX, but see that the relay is only rated for 30VDC (DC up to 30VDC: 3A). What is the rationale behind limiting the ekrano relay output when the Ekrano itself can (and commonly is?) powered by 48v systems?

Relayekrano gx
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

2 Answers
Alexandra avatar image
Alexandra answered ·

@jamierob

Your GX is your system controller. They are designed to signal not carry loads.

Running DC loads always has contact arcing on open and close. People installing should be using external relays (which is safer and a better design) for running external loads so the spec is so.

3 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

atebee avatar image atebee commented ·
The OP is switching the load via the Solid Switch. But at a system voltage of 48v the relay on the Ekrano can't be used as the control for Solid Switch.


The Ekrano relay not being able switch 48v is a frustrating limitation given how common that is as a battery system voltage.

0 Likes 0 ·
Fideri avatar image Fideri atebee commented ·
I'm not familiar with the Solidswitch but I use other DC-DC relays. They take a DC signal to switch DC loads.

I don't understand why the OP or anybody can't use 48v from the battery to switch a large DC or AC load via GX which sends the required control signal to an external relay.

The Cerbo relay eg can take up to 70 vdc to send a control signal. This means you can use a 48vdc battery. So where is the problem?

F.

0 Likes 0 ·
atebee avatar image atebee Fideri commented ·
The Ekrano can only take up to 30VDC on the relays according to the spec sheet.
0 Likes 0 ·
Fideri avatar image
Fideri answered ·

@Atebee You are right. I now see the point. As a work around, one can use a separate power supply such as for a laptop. But that means additional equipment, wiring, etc.

F.

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Related Resources


Ekrano GX product page.

Ekrano GX online manual

Ekrano GX datasheet

Additional resources still need to be added for this topic

Additional resources still need to be added for this topic