Electronics > Metrology

Plagiarize Keysight b2983

<< < (4/4)

julian1:
A comment on both boards. It is curious to see all the guarding, and cutouts, while also employing signal relays (datasheet suggests 1G insulation resistance), rather than reed relays.

Maybe the signal relay coils, and pole node, are driven by isolated/floating signal relays. The digital board of the agilent has a bunch of reed relays, so perhaps that is the strategy used. 

bsw_m:

--- Quote from: julian1 on August 18, 2022, 10:27:49 pm ---A comment on both boards. It is curious to see all the guarding, and cutouts, while also employing signal relays (datasheet suggests 1G insulation resistance), rather than reed relays.

--- End quote ---

The AGN210 series relays are adequate for the application of this device. They have an insulation resistance between open contacts > 100 PetaOhm and an insulation resistance between the coil and all shorted contacts > 100 TeraOhm. (Data from actual measurements of a certain number of these relays)
These relays also provide reliable contact for switching low currents/voltages.
The main disadvantage of these relays is the absence of an electrostatic shield between the coil and the contact groups, so that they have a very high charge injection from the control (when the relay is switched).

P.S. The Hongfa relays used in the Tonghui electrometer have comparable parameters with the Panasonic AGN210 series relays
P.P.S. For comparison, the insulation resistance between the open contacts of the electrometric reed relay TRY-204S-14 manufactured by Okita is about 2 PetaOhm

Navigation

[0] Message Index

[*] Previous page

There was an error while thanking
Thanking...
Go to full version