please help a newbie out

Thread Starter

jay.diem

Joined Jan 12, 2009
10
Realize this is a really simple question, but I just want to make sure I'm reading the datasheet correctly.

Will 22VDC across the coils be sufficient to trip this relay?

T9AP1D52-24

Datasheet: here

Kind of confused about the "must operate voltage" and the "Must release voltage". :confused:

Thanks.
 

Audioguru

Joined Dec 20, 2007
11,248
The "engineers" at Tyco think that their relays will operate with a voltage as low as zero V and release with a very high voltage.
They should go back to school.
 

eblc1388

Joined Nov 28, 2008
1,542
After a bit of more careful researching on the NET, I have found out more information regarding the issues.

The same "error" appears on three more Tyco relay datasheets I looked at and also appears on those from Panasonic relay and Omron relay datasheets. So there must be something we don't normally aware.

Perhaps we have owed the engineers at Tyco an apology.

I'll give an example to illustrate the situation. Suppose the engineer tests a batch of 5 relays for the min. operating voltages and result comes back as 75%, 70%, 60%, 62%, 65% of nominal rated coil voltage. Therefore it is correct to say that the "operate voltage" is 75% or possibly less. But there is no guaranty that a single relay will operate at 70%.

Therefore, as a circuit designer, one should design a circuit that ensure the relay operating voltage never go below 75% but as a relay manufacturer, the specification is to show that 75% is the worst case condition and many relays produced will also operate even at lowerr voltage like 70% or maybe 65%.

This is now a problem of semantic, both of these statements are correct:

1. Operate voltage is 75% or less. (note: no "MUST")

2. Must operate voltage is 75% or more.

So it appears the use of the qualifier "Must" causes the statement #1 to become false.

I hope this will now put the issue to rest. :(
 
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