APX-BC400 PTP Slave Clock Module
Product Overview
The APEX APX-BC400 is a PTP slave clock module for equipment and network segments that receive time from upstream rather than generate it. It recovers IEEE 1588v2 time and phase from a grandmaster, filters the jitter that the packet path introduces, and passes a clean reference on to the devices that depend on it.
Phase distribution is a chain of relays, not a single decision. One grandmaster serves the network, but the equipment that needs the reference is spread across many nodes, and a node that simply forwards the packets it receives passes the delay variation of the path along with them. The result is a reference that looks present at every point and is worse at the far end than at the near end, which is exactly the case that causes trouble in time division duplex radio and in measurement environments.
The APX-BC400 sits at that node. It locks to the upstream grandmaster as a slave, and either terminates the reference or acts as a boundary clock, regenerating time and phase for the ports that face downstream equipment. Its own oscillator keeps the reference stable during short interruptions of the upstream chain, and it can also take a GNSS input where a satellite view exists at the location. Outputs cover PTP on its own ports, 1PPS, 10MHz and time code, so equipment that does not read packet time can still be synchronized from the same recovered reference.
It is used inside transport equipment and at network edges where a full grandmaster would duplicate a reference that already exists in the network, in industrial and measurement installations that take time from a central source, and in projects that distribute a single traceable reference across a wide network in defined steps.
Key Features
- PTP slave clock function with boundary clock operation for downstream ports
- IEEE 1588v2 time and phase recovery from an upstream grandmaster
- Jitter and delay variation filtered at the node instead of being passed downstream
- Holdover on the internal oscillator through short interruptions of the upstream chain
- Optional GNSS input for locations where a satellite reference is available and continuity matters most
- 1PPS, 10MHz and time code outputs for equipment that does not read packet time
- NTP and SNTP service available for management systems and servers at the node
- Reference priority with automatic switching between upstream and local sources
- Status and alarm reporting for lock state, source and holdover
- Module and rack mounted variants for integration into equipment or installation in a bay
- Configuration recorded per project, so repeat nodes are set up identically
- CE and RoHS compliant, supplied with a test report and a 3 year warranty
Technical Specifications
| Specification | Detail |
|---|
| Part Number | APX-BC400 |
| Product Type | PTP slave clock module |
| Protocol | IEEE 1588v2 PTP, slave and boundary clock operation |
| Upstream Reference | PTP grandmaster over Ethernet |
| Local Reference | Optional GNSS input where a satellite reference is available at the location |
| Packet Outputs | PTP on downstream ports for equipment that recovers time from the packet layer |
| Physical Outputs | 1PPS, 10MHz and time code outputs |
| Network Time | NTP and SNTP for management systems and servers |
| Holdover | Internal oscillator, maintained through short interruptions of the upstream chain |
| Redundancy | Reference priority with automatic switching |
| Management | Web interface, SNMP and alarm reporting |
| Form Factor | Module and rack mounted variants |
| Configuration | Interfaces and profiles set for the project before shipment, configuration recorded |
| Application | Transport nodes, network edges, industrial and measurement installations |
| Compliance | CE, RoHS |
Applications
Transport Nodes and Network Edges
Regenerates time and phase at the point where the reference would otherwise degrade, so downstream equipment receives a reference of the same quality as the node nearer the grandmaster.
Industrial and Measurement Installations
Takes the reference from a central source and passes it to controllers, recorders and measuring equipment that need time and phase but cannot lock to a grandmaster directly.
Multi Step Reference Distribution
Used where one traceable reference has to reach a wide network in defined steps, with each node regenerating the reference instead of forwarding delay variation with it.
Deployment and Selection Notes
Decide where the reference is generated and where it is merely repeated. A grandmaster is needed once; beyond that, each node that must not degrade the reference needs a slave or boundary clock function. List the downstream equipment at the node, note which of it reads packet time and which expects a discrete signal, and the APX-BC400 is then configured to that list.
Consider the upstream path as part of the design. The quality that arrives at the node depends on the path that feeds it, so the number of hops and the load on those links should be known before the node is configured. Where continuity is critical, a second reference path or a local GNSS input is used and the priority order is set so that the intended source is the one in use.
The rest of the range covers the other roles in the same plan: PTP grandmaster clocks where the reference is generated, GNSS and NTP network time servers where network time alone is required, timing modules where synchronization has to be embedded in equipment, and synchronization systems where a multi site deployment is planned as one project.
Compatibility
The APX-BC400 interoperates as a slave or boundary clock with standard IEEE 1588v2 equipment and serves downstream devices over PTP or through 1PPS, 10MHz and time code outputs. Send us the grandmaster type, the downstream equipment list and the profile in use, and we confirm the interfaces, the profile configuration and the form factor in one document before the order is released.
Related Products
Frequently Asked Questions
When is a slave clock module the right choice instead of a grandmaster?
When the network already has a traceable reference and the requirement at this location is to relay it without degrading it. A grandmaster is used where the reference is generated; a slave or boundary clock is used where it is carried forward.
Does the module need its own antenna?
Not necessarily. The primary reference is the upstream grandmaster over Ethernet. A GNSS input is optional and is used at locations where a satellite view is available and continuity is critical.
What happens if the upstream reference is interrupted?
The module holds over on its internal oscillator and switches to the next source in the priority list, reporting the change of state so downstream impact is known at the time.
Can it serve equipment that does not read packet time?
Yes. 1PPS, 10MHz and time code outputs are available alongside the PTP ports, so non-packet equipment at the node is synchronized from the same recovered reference.
Why Choose Apex
- Reference quality maintained at the node instead of degrading further down the chain
- Slave and boundary clock operation, with the profile and interface list confirmed with you before the order is released
- Module and rack mounted variants so the same function fits equipment or an installation bay
- Lock, source and holdover state reported, so the network reference is monitored end to end
- Backed by a 3 year warranty and technical support on synchronization planning and topology
