American Power Conversion PMH3XLM user manual Relay Contact Pin Arrangement, Dry Contacts

Dry Contacts

The PMH3XLM includes a set of Dry Contacts available at a terminal block at the right-front of the inside panel. This feature provides two sets of normally open (NO) and normally closed (NC) contacts which can be used for remote monitoring of the PMH3XLM’s operating status by changing state when there is an alarm condition. Examples of remote monitoring equipment include a computer interface board, emergency management system, or APC’s Environmental Monitoring Unit Option (see Environmental Monitoring Unit Option). The relay contact pin arrangement is outlined in Table 2. (Note: The jumpered connections of Pins 7, 8, & 9 do not represent a third set of contacts).

For applications using Dry Contacts, please note the following information:

•The Dry Contacts are designed for low voltage or control signals only. The maximum switching current is 1 amp. The maximum switching voltage is 24 volts, DC or AC.

•Higher energy applications may require additional relay implementation outside the PMH3XLM. Damage to the PMH3XLM unit’s relay caused by implementation with energy levels in excess of those discussed in this manual will not be covered by warranty.

Note that the Dry Contacts will allow the PMH3XLM unit to communicate with one (1) external device.

Table 2: Relay Contact Pin Arrangement

Relay Contact

Set 1

Form "C"

Relay Contact

Set 2

Form "C"

Pin

1

2

3

4,7

5,8

6,9

Contact Type

Normally Closed (1)

Common (1)

Normally Open (1)

Normally Closed (2)

Common (2)

Normally Open (2)

NOTE: Pin pairs 4 & 7, 5 & 8, and 6 & 9, are connected via jumper internally. The combined current of each pin pair may not exceed 1 Ampere.

Environmental Monitoring Unit Option

APC offers a Environmental Monitoring Unit Option, which allows the user to monitor the alarm status of the connected SPD. The product is available as a 120-volt external power supply (AP9312PM) or as a 100-240 volt universal input external power supply (AP9312PMI).

The AP9312PM is connected to the SPD using Dry Contacts. When an alarm is triggered, the Dry Contact closes and the Environmental Monitoring Unit Option sends up to four e-mail messages to preprogrammed addresses, notifying the address that the SPD is in an alarm condition. The e-mail messages can be sent to computers, pagers, cell phones, or Palm® Computers anywhere in the world over the internet.

The AP9312PM has its own internet protocol (IP) address and is usually connected to a 10Base/T communications network. It then uses its internal browser software to host a web page on the internet. Facility managers can monitor the status of the Environmental Monitoring Unit using their computer and internet browser, such as Microsoft® Internet Explorer®. An qualified/licensed electrician is required for installation of the Environmental Monitoring Unit Option to the Dry Contacts of the SPD.

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